I love to ride. When I lived in a (far) more bike friendly city I rode to work and loved it. After leaving that city I loved nothing more than an hour on a bike at the gym.

This morning I found out that a charity very close to my heart is having a 70 mile road event in October and I've decided that I'm going to take part.

I badly need some help. I've read dozens of sticky threads, dozens of FAQs, and I'm no closer to step one, which is finding a bike. I'm 6ft tall, need a road bike which can handle some gentle urban hills, is suited for longer distance riding, and would like to keep bike + accessories around $600. Which could be crazy, but I have absolutely no idea, no frame of reference.

What I really need is someone to point me at a bike which fits my needs and says "this will work for you", since I'm just lost in a sea of biking related firefox tabs.

Help, please?