Wellbutrin definitely can have some nice peripheral effects- I'm curious as to how you describe your anxiety, though. You have GAD as a tag but only mention social anxiety and avoidant personality disorder. How you describe your anxiety in more detail? Plenty of physical terms, any mental ones? (Evaluatory thoughts? Self-contained observance? Worry? [Defensiveness] That wonderful sense of judgment?) Or some combination, like types of tension.
I was on 300-375 of bupropion, (75s from starting out- I usually go very slow with medicines, but ramp up pretty high. Ex. 5mg Prozac to 80mg.) and had a strong tremor going on, especially in public places, along with the same sort of edginess you described. Part of what helped me was removing part of the self-analysis and expectations and instead describing things in the environment or playing mental games, but only after a long period of work with a therapist and a few different medicine combos. (Buspirone helped at lower doses, along with lithium, although I know both of those didn't seem to work for you. Augmentation and a relative goal path seem to help.)
There's a pretty interesting recent study with buspirone and melatonin as well.
http://www.ncbi.nlm....pubmed/22998742 Equally so, depression was a bigger problem in exacerbating my social anxiety, and the wellbutrin didn't quite cover it. Now I'm on Parnate (70-80mg) and still working in a few different therapies. (CBT by itself wasn't that great with removing negative analysis at some levels, or with stopping the nullification of positives, for me.) I wouldn't suggest Parnate, as it isn't an easy drug, and it didn't especially help my anxiety. Oddly enough though, I started low-dose naltrexone as part of my depression regimen, and my social anxiety has been much better. (Which is weird as I tried low-dose naltrexone before, and it didn't seem to do anything.) Combinations and time seem to be important.
I guess I would ask what sort of social experience you hope to have, and what timeframe you see for the problem. Considering the amount people think about other things in social situations, just framing another person's mindset, at least in a rough sense, can be great.
Definitely agree with the post above as well. For breaking heavy sweating, tremor, panic, and really high pulse though, most people go for a course of benzos at first. Absolutely needed to break some awful cases of anxiety, as people can get a break and transition to a different course. Even a quarter of clonazepam may work for some at first.
You have had a break from social anxiety though, and that is really good. And you're posting, which is a lot better than some social anxiety. (I find it very difficult to even approach that sort of contact from time to time.)
A course of time and choice of bearable side effects, with realistic expectations, may be the best was to go in a long course of trials of medicine. Getting used to the feelings of discomfort and working from there. More medicines will come out in time.
Sleep deprivation reversal does point to ongoing depression.
[Also, L-theanine wasn't all that great for me- really weird with socialization. Lot of distance.]
Good luck.