Finding a new pack amongst the many cottage manufactures can be a difficult and somewhat expensive (shipping costs!) adventure. Buying from REI or EMS has a definite advantage, considering you can try out the pack in-store and more importantly have the security of the no questions asked return policy. From what I've seen, the real only lightweight options they have are osprey (exos/talon) and granite gear (crown VC, blaze AC).
When looking at cottage packs, there seems to be much more variance in the quality and most importantly the suspension system. For someone without a ton of lightweight backpacking experience, the suspension system my main problem.
I have experience with Gossamer Gear, ULA and HMG. If you are really intent on getting the right pack, I'd recommend getting the candidate packs in two sizes, unless you are absolutely sure. Gossamer Gear seems to have everything in stock, and will ship items very promptly, great customer service. For ULA, I bought from next adventure http://nextadventure.net/camping-and-hiking/backpacks/?subcats=Y&features_hash=V890 because they have free shipping and a 30 day return policy, they shipped the pack pretty much the next day I ordered. Lastly, my HMG pack took a little longer to ship out (approx 1 week), and their return policy isn't as flexible at only 15 days.
Keep in mind that if you find the pack just doesn't work for you after using it (most return polices stipulate that the bag be in never used condition), you can always sell it here on gear swap for usually around 80-90% of the purchase price.
Gear swap is also something you could look into, assuming you don't need it now, as people tend to sell used packs for up to 50% off. This would give you a nice cheap avenue towards trying out a cottage pack.