Tera, it depends on the college. Some want homeschoolers to take an extra test or two. MANY are very anxious to get homeschoolers. Homeschoolers attend college because they want to be there, rather than its just being the next step like lots of students. They know how to learn independantly, which is an important skill for college students. They've often done very interesting things.
There are a lot of ways to prepare transcripts, and different colleges have different expectations. Colleges as esteemed as Stanford, Yale, Harvard, MIT, etc. regularly accept homeschoolers.
One book we're finding helpful is Loretta Heuer's The Homeschooler's Guide to Portfolios and Transcripts.
If you care, I have a couple of short articles in the book The First Year of Homeschooling Your Child: Your Complete Guide to Getting Off to the Right Start by Linda Dobson. It's a neat book for new homeschoolers, but perhaps I am biased.
Kathryn