Hi Josh,
Check out AR15.com they have dedicated forums, including step by step pictures & instructions on how to build your own AR-15. Building the lower is very simple and would make for a great project for you and your dad. The upper receiver build is a little more tricky, as you'll need some specialized tools, but again, the instructions on AR15.com are very good. You can also purchase "How-To" DVDs on-line or from AGI.
As other posters have said, your $2000.00 budget is quite generous and will certainly permit you to purchase a complete rifle quite easily, even a new-in-box model.
As for "brand" names, I'd stick with Colt, LMT or STAG, in order of preference. While the Colt Law Enforcement series of rifles are quite expensive and hard to obtain here in Canada, their standard sporting & HBAR rifles are much more common and there are some excellent bargains to be had in the CGN EE.
LMT is also an excellent maker and you can source their products from Questar, a contributing dealer on this website. I currently own both Colt and LMT ARs and believe me, the LMT gives nothing up to the Colt in terms of quality, ruggedness, accuracy or reliability
STAG is another of the top tier AR makers and Walter from Arms East offers just about their full line of complete rifles and parts. He's another contributing dealer and is great to deal with. If you and your dad decide to try and build your own AR lower, you can do much worse than to purchase a stripped lower from Arms East, along with a "lower parts kit". He can even set you up with a six position "CAR" style collapsible stock and all the fixings. I recently finished putting together a STAG lower for a shorty AR build project I have ongoing. I'm very impressed by the quality of STAG products, moreso than that of many other "big name" manufacturers.
If you're looking for a different stock with a higher "look cool factor" there are many other dealers here on CGN that carry AR parts and accessories; however, the Equipment Exchange is a great place to look, especially for harder to source parts like Magpul M93B, CTR, VLTOR stockes, etc... Many of the new picatinny rail handguards, free float tubes and other uber-cool "tactical" accessories are also available from many CGN sponsoring dealers such as Wolverine Supplies, The Shooting Edge, Dave's Surplus, Arms East, etc...
Good luck with the build!
( lol I bought a sig sauer mosquito for my first handgun and a nikon buckmaster 6-18x40mm for my tikka and now the rest is goin towards driver's ed and tithings to my church and I should have roughly 200 dollars left in the end that will get me on a start
