In the heat many prefer external frame packs. The Kelty linked to earlier is a tried and true tested design.
If you are only warm weather backpacking a down quilt will keep you comfortable into the 50's. A typical rule of thumb is choose a bag giving you 10 degrees of cushion below the low temps you expect to see.
Both my sleeping bags are down filled, they are lighter and more comfortable than synthetics, YMMV.
Get either merino wool base layers or decent synthetic base layer underwear, REI and Patagonia both make good stuff. My favorite underwear for hiking in are Ex Officio boxer briefs. I only use Smartwool brand socks to backpack in. Taking care of your feet is of the utmost importance! Your boots are going to be critical, make sure they are well fitted to your feet. A boot that works dayhiking may not work when you load an extra 40lbs on your back.
You are tall so you will need a two man tent most likely as a solo shelter. A lot of taller/bigger guys use tarps for that reason. Personally I want my nighttime shelter to be a barrier from the bugs. I use a two man tent as a solo shelter because I want to be screened in from the bugs. There are a couple solo tents out there that are big enough for me I just haven't dropped the cash on one.
REI sells "Ruff Wear" backpacks for dogs.
Here is a typical gear list
http://www.backpacker.com/spring_summer_fall_gear_checklist/gear/12107?page=1