On my last post about my refinished desk, I was asked a question about how I did it. I started to give a quick response in a comment, but I decided it would make a good post. So here is the skinny (or probably not so skinny) on refinishing wood.
1st - you have to consider what kind of condition the wood is in and how you want the finished product to look. If you are painting it you just need to scuff in up a little with sandpaper. If you are staining it the wood will need to be completely stripped with some kind of chemical stripper.
If you are painting it and want the piece to be nice and new-looking, fix any holes or cracks or dings with wood putty. Let it dry and sand it flush. I'm not sure of the exact process for fixing imperfections if you are planning to stain the wood.
I like a more aged and worn look, so I leave the dings and cracks as they are. I think it adds character.
Next - If you are staining it, just rub the stain on, wait a bit, and rub off the excess. Then seal it with polyurethane or wood wax, and you are done.
If you are painting, give a good even coat or two of primer (I like the spray - it's quicker and easier). If you are painting, you need to use a good primer to cover the entire surface. There are different color primers. Basically, if you are painting a light color use a light color; if you are painting a dark color, use a darker primer. Easy enough.Then just paint and enjoy!
Tips (learned from experience):
Paint with primer in it does NOT equal a primer coat. You will have problems with pealing.
Black stain is not really black. If you want black you have to paint.
For the desk I just finished I didn't do any surface repairs. I painted the body with Kilz Semi-Gloss Bulgar Wheat paint. (The guy mixing the paint kept calling it "Burglar Wheat" hehe.) Then I mixed 1 part water and 1 part Ralph Lauren Satin Ebony paint and used it as a wash for the desk surfaces so the wood shows through just slightly.
Hope this was helpful for anyone starting a refinishing project. Good luck!