Alright, I just purchased an older cannondale as shown

http://cgi.ebay.ca/ws/eBayISAPI.dll?...m=220393173187

I want to do some upgrades that will be the most beneficial / easy. I bought "Zinn & the Art Of Road Bike Maintenance" for some literature before I start.

My question is what should I start with? I have about $500 on top of what I paid for this to transform it into a decent bike. How difficult are carbon forks / carbon handlebars to install? The bike has new cabling and a new tire. It was listed as the gears not working after the maintenance on the bike; could that be due to cable stretch? The components are campagnolo, which as expensive, so I guess $500 wont goo too far?

Thanks!