This sounds simple, but the key is to avoid phone interviews. I'm terrible on the phone as well, and when I was looking for my last job I thought about this a lot. Looking back, I had received a job offer about 90% of the time when I had a face to face interview, but for phone interviews it was more like 10%. With that in mind, I focused on getting in person interviews the last time and found that even if someone asks for a phone interview, often you can ask/convince them to do a in-person. This might mean you have to travel on your own (or maybe they'll pay for it), but by knowing your previous rate of success you can focus on getting the job you want.