Ok, start with the kits on this page, avoid the "rock" kis for obvious reasons:
http://www.baileysonline.com/search.asp?SKW=climbing kit&catID=1393
Now, see what's in there? Look around and see if you like a diferent saddle, rope etc. it's never good to use spikes on a trim, it's always good to use spikes on a take down. Keep in mind a "split tail" will be very handy for making your pruisic knot, which ever you choose. I still climb on a Blakes hitch, simple and effective for my fat azz!
You will need another hank of rope for a bull rope no matter what, I need to get another one even. Buy Arborplex for that, it's tough as nails, strong as a bull and cheap.
As you go you will need some slings, and I would recomend a chainsaw lanyard, I wont climb without one! I like the bung style that breaks away, gets the saw away from me if I need to drop it.
Get plenty of 'biners, plan on paying $25 each, and have at a minimum of 3.
Get the "Tree climbers compainion" by Jeff Jepsom. Read it, read it again, read it again, read it until it's in your head, you dream about that book!! Get a chunk of rope and take it everywhere. Practice your knots every chance you get.
THEN try climbing a tree. go slow and stay low. Learn how to hip thrust then work to foot locking. You will look like an azz for a while, but get over it!!! Practice this, ask more questions, then work your way up a tree. Lear to reposition in a tree. Learn how to do a re-direct in a tree keeping the original TIP and using the tag line of your rope.
Set up a crotch line and tie your bull line up in the tree a few times.
THEN, if you still feel comfortable, and think you want to do this, take a saw up and do a trim job.
I know how hard this is to learn alone, I did, and am still learning daily.
It's not for everyone!! There are days I love being in the tree. There are days I can't get out fast enough!!!!
Look like something you want to do?