the epa has a good section on lead stuff in general. Small areas are not a problem if you do the research and know the right methods. but professional abatement companies can often do it at a reasonable cost and are certainly the way to go for big projects. I'ts kind of like drywall. you could do it yourself, but if it's a whole house or a few rooms your probably better off leaving it to people who just do that.
Check all the regs too- the buyers will.