AIRFLOW:

Its good your starting the great sport of fly fishing, i myself started it some 50+ years ago and i haven’t looked back on it since. It also makes a change an anger willing to use a fly to catch trout than some artificial plastic in a tub made by Berkley. Now to help you out. Without over complicating things here, you need to see what is happening around you in the water, look to see if there are any hatches of these flies that are stuck in the surface film of the water trying to emerge. If you notice this then a CDC suspended emerger type pattern can work well as trout pick these emerging insects from the surface.
You must also take into account temperature, weather conditions and time of year.
generally in the warmer summer months there will be allot more hatches than that of colder winter months, wind can also reduce the amount of hatches. Fishing on overcast days is one of the best times to fish for trout. If you can see these hatches then you need to go straight to a dry fly, try all the ones you have and try to match them to any real ones you see on the surface.
Fish them on a floating line, with a mono-filament leader(don’t use fluorocarbon because it will sink your dry fly). If your fly sinks you may need to apply a little gink. If the water is colder and there are less hatches you may want to use a nymph. Standard nymphs like pheasant tail nymphs and hares ear nymphs are great fish them on a floating line, subsurface, dont retreive them just occasionally twitch them fish them under an indicator to help bite detection. If you get no takes with these go for the wets, examples are the typical woolly bugger, fish it on a intermediate line with a flurocarbon leader, retrieve with a slow figure of eight.

LOTS of info here, dont let the name stop you it is fly fishing
http://www.sexyloops.com/advice/index.shtml

http://www.virtualflybox.com/

All of the items including flies, tippets, floatants and indicators are available here, its good to look them up so you have a picture to go with the name and pick up any advice you can
http://www.cabelas.com/cabelas/en/templates/category/category.jsp?id=cat20431&cmCat=MainCatcat20431&navAction=jump&cm_re=LeftNav*FlyFishing*052308

*added*
You might also like to look at this, taken from another fly fishing question very similar to yours.

From the end of the fly line down to the fly, follow these steps and you should catch. For tippet material you have a large choice because first there are leaders then there are tippets for general fishing tippet i use fluorocarbon as its invisible in all water and suitable for saltwater too, for makes i always go for airflo sight free g3 which i generally buy from cabelas, second are leaders these are tapered towards the tip and help yo achieve a better turnover (cast and presentation) these i don’t often use but when i do i use Cortland fine trout leaders in clear, these are good for a beginner such as your self as the dont often need changeing and help you cast further than before with a neat presentation what i will say is dont use flourocarbon for dry flies as it will make them sink, you can use it so long as you put a floatant on your dry such as gherkes gink or loon, aquel i buy lots of my gear from cabelas and bass pro
firstly airflo tippet
http://www.cabelas.com/cabelas/en/templates/product/standard-item.jsp?id=0043719317701a&navCount=1&podId=0043719&parentId=cat600599&masterpathid=&navAction=jump&cmCat=MainCatcat20431-cat20439-cat600599&catalogCode=IJ&rid=&parentType=index&indexId=cat600599&hasJS=true
Leaders and cabelas own brand is fine for this
http://www.cabelas.com/cabelas/en/templates/pod/standard-pod-wrapped.jsp?_DARGS=/cabelas/en/common/catalog/pod-link.jsp_A&_DAV=MainCatcat20431-cat20439-cat20510&rid=&indexId=cat20510&navAction=push&masterpathid=&navCount=4&parentType=index&parentId=cat20510&id=0036480

gink floatant (better than loon)
http://www.cabelas.com/cabelas/en/templates/pod/horizontal-pod.jsp?_DARGS=/cabelas/en/common/catalog/pod-link.jsp_A&_DAV=MainCatcat20431-cat600029_TGP&rid=&indexId=cat600029&navAction=push&masterpathid=&navCount=7&parentType=index&parentId=cat600029&id=0011254
Dry flies that should work in your area
http://www.cabelas.com/cabelas/en/templates/pod/horizontal-pod.jsp?_DARGS=/cabelas/en/common/catalog/pod-link.jsp_A&_DAV=MainCatcat20431-cat20528_TGP&rid=&indexId=cat20528&navAction=push&masterpathid=&navCount=10&parentType=index&parentId=cat20528&id=0030430
* when you use a tippet for freshwater i generally go for about 5lb but as a beginner you can use up to 10lb with airflo g3 and still catch.

I would try mainly nypmhs however if you arent confident in dry fly fishing or if the trout arent rising, some great flies to try for a beginner like yourself would be
The Pheasant atil nymph, anything from size 12-14
hares ear nymph same sizes, also a gold bead head version can work equally well, when fished closer to the bottom.

http://www.cabelas.com/cabelas/en/templates/pod/horizontal-pod.jsp?_DARGS=/cabelas/en/common/catalog/pod-link.jsp_A&_DAV=MainCatcat20431-cat20530_TGP&rid=&indexId=cat20530&navAction=push&masterpathid=&navCount=15&parentType=index&parentId=cat20530&id=0017062
These can also work well fished very close to the bottom on a floating line, try a co-polymer leader
http://www.cabelas.com/cabelas/en/templates/product/standard-item.jsp?_DARGS=/cabelas/en/common/catalog/item-link.jsp_A&_DAV=MainCatcat20431-cat20530&id=0030347313208a&navCount=17&podId=0030347&parentId=cat20530&masterpathid=&navAction=push&catalogCode=IJ&rid=&parentType=index&indexId=cat20530&hasJS=true
The san Juan worm is one to try, fish it singly with a almost static retrieve, twitching it every minute or so.

if all else fails you may want to try a woolly bugger like this
(it has built in flash to add a little more appeal)
http://www.cabelas.com/cabelas/en/templates/pod/standard-pod.jsp?_DARGS=/cabelas/en/common/catalog/pod-link.jsp_A&_DAV=MainCatcat20431-cat380001&rid=&indexId=cat380001&navAction=push&masterpathid=&navCount=20&parentType=index&parentId=cat380001&id=0023260
Hope this is of help.

JustAsking:

http://www.amatobooks.com Good luck to you on fishing.

MVP:

Trout fishing I approach a little different than bass.

I don’t fish lakes, but in rivers when trout fishing I always use bread. It seems to be the best bait for me and others whom I’ve fished with but here’s my technique.

Put a sinker on your line about 4 inches above the hook, but a little tad bit of bread completly covering the hook (so that the trout doesn’t see it). Cast into the deepest part of the river and let it sink, barely reel in your line so that it stays good and tight. And if you feel one nibble, just let it set, it’s getting a good taste of it.

I’ve caught thousands of trout throughout my day and can tell you bread is by far the best bait from my experience.

I hate lake fishing though, never any luck. I’ll catch 100 in a river before I’ll catch 10 in a lake.

Last trout fishing I did, was last Saturday and caught 35, alone. My buddy caught 40. This was in a number of about 5 hours.