Good for you! Might as well challenge yourself.

We don't have any mountain bike racing near here and I can honestly say I have never ever been interested in racing a bike, any sort of bike. Until lately I wasn't interested in racing at all but I entered myself in a local 10K running race in November and surprised myself how much I enjoyed it and how much motivation it gave me to train that I'd never had before (just as well with the weather we've been having). I've entered a couple of more runs early next year to keep things going.

Still not interested in short course XC racing but fancy doing some short adventure races and MTB enduros next year (SO doesn't know this yet!).

I'm not sure about "training" as such as I've never trained before, just gone out riding, so I'll be interested in any info that comes out here as I've found following a structured training plan for running has had real benefits.