that's no huge feat for even a newbie. you just have to have the cone washers and axle...though i'm not sure how to tell you to measure it. one option is to take it to your LBS, buy the parts with them but say you'd like to learn to do it yourself. they should be alright with that, you're still giving them business that you wouldn't have if you had ordered online.

watch out with when you install the new axle, you'll likely need to repack the hubs. actually, for a new wrench this may get a bit involved... i'm really not sure.