Luckily there are many alternatives to PS. I'm not sure what's the best, but I've heard of paint.net, GIMP, and a bunch of others. If you look around, you'll find a big list of them on the web.
Yeah I tried to use GIMP, but it isn't user friendly at all. Paint.NET is a lot more easy to handle (it isn't as complex as the GIMP but it's enough for me)
Thanks guys, I'm downloading the GIMP right now, paint.net I'll get on my other computer, but right now im on my old computer, (it's a windows 2000 and paint.net needs xp >.<, but at least my other computers an xp...)
Most major computer-oriented electronics stores should stock them. Of course, for goods like these I recommend shopping for it online.
The commercial benchmark is Wacom. The cost depends on the model- essentially meaning size and levels of touch sensitivity. The more serious you are about your art, the more you should think about forking out.
For example, I would want to get a Wacom Intuos 3 9x12i. Problem? That's gonna set me back about 500-700 bucks. Getting an A4 sized high-quality tablet is a bit hardcore though; if you want something light, quick and easy, you could look at an $80 Bamboo.