Danielle, are there any no-kill shelters near you? Have you searched on line? Can they take in a pregnant female?
You can click on the link in my signature line and it will take you to resources where you can search to find out. Although the actual yellow pages or the Yahoo yellow pages are often very helpful too.
If your area is anything like ours, the no-kill shelters are full. Unfortunately, she's pregnant again, so you can't have her spayed now. Do you put food out for the cat? Does she belong to someone or is she stray or feral?
The answers to these questions will affect further advice.
Just FYI, you can contact your vet, or vets in your area to see if any of them will lend you a trap. Trapping hints are here: Helping Ferals
You can also contact your vet or other local vets to find out if they know of any "crazy cat people" in your area who may be able to help. Don't feel embarrassed asking the question - there is usually at least one in most communities, and some vet will know who it is. Sometimes even the vet will help.