Free: Contests & Raffles.
Agree, stick with glass that is the same brand as the camera you choose.
I've heard nothing but good about Pentax and would consider it for its reputation for durability and weather proofing if you're considering serious outdoor work. Hit up some of the forums on Photography on the Net or DPreview with questions. You might consider waiting until Black Friday and what not. I bought my 6D last fall around that time and the camera still costs more if you buy it today even though digital cams tend to have 3-5 year product life cycles anymore. Put your neck strap in the fireplace and don't think twice. I use a wrist strap when carrying my camera. If you're going to be humping mountains with trekking poles you should probably consider backpacking it and maybe using a sling.