Canon and Pentax use the same wired remote - it's just a 2.5'' headphone jack (like cell phone headsets). Short one side and it focuses, short the other and it trips the shutter. It's pretty trivial to make your own, but you can buy made-in-China ones for almost nothing. Check Meritline or Dealextreme for a wide variety. You can also get wireless ones from them. You could probably get both for $5-10 shipped. (Probably a lot closer to $5!)
I picked up a cheap Dealextreme wireless and it works fine (also works with any manufacturer), but I've never used it in a real-life shooting situation. The wired one is better for things like fireworks shooting.
Whether or not your remote works in the back depends on whether or not you have an iR sensor on the back. Generally, entry-level DSLRs don't and high-end ones do.
You can always pick up the factory battery grip, which includes a spot to stash the F remote.