Clutch lever won't engage

[sixpack_sid]

I have an 85 Honda ATC 200 X 3 wheeler. When I engage the clutch lever, it doesn't spring back. I have to push it out with my fingers and then the bike doesn't go. I just got the bike and this is how it was when I got it. I had it out the other day and now I can't get it to shift out of any gear. It's stuck in 1st gear. Any ideas what the problem is or what I can look for? I would like to get this fixed in time for snow season.
Thanks for the help!

[rt20ps]

Sounds like the clutch plates are stuck or broken. Pull the cluch cover and inspect..

[sixpack_sid]

After further investigation, I could see that the clutch cable was rusted fast. So I ordered another one, and just put it in this weekend. I started her up and when I popped it in gear-it shut off. So appartantly, the clutch isn't disengaging. So I took RT20PS advice and popped off the clutch cover. But I cannot break the screws loose on the oil filter rotor cover. They are starting to strip on me. I have a repair manual, and see that there are special tools needed, a gear holder and a clutch center holder. It says the gear holder is not available in the USA. Am I getting in over my head? I'm not too familiar with it, and I thought with the manual I could replace the clutch, but I can't get the oil cover off. Is this something I can tackle myself or should I call the mechanic?
Thanks for the help!