Are there barrels out there that you can just switch out like other 10/22 barrels? Do you need a different clip? Or is this a big gunsmithing job?

All you need is a barrel and heavy bolt handle.
A 15 min job at most. If you don't have a bull barrel stock then take a look a houge's as it is both cheap and works great. Eabco has the barrel and bolt, a Shaw I believe. Use your clip.
http://www.eabco.com/hornady17hm2.html

Actually, check out what is offered for $200.00 or so on Boyd's Gunstocks web site...

The 17 Mach 2 is too spendy in my book for conversion in a 10/22.....

I take kids out shooting at the range that go thru a couple of boxes of 550 rounds per box in a couple of hours....So I have to stick with 22 LR...

Worth a look/see also....

cheers
seafire

I did the EA Brown conversion and love it!! It cost about $160 I think, but it shoots better and farther than the 22 LR by a wide margin. It is more expensive to shoot, but that just makes me plink with my Rem model 12 short and Model 24 Short...life is tough!!