Out of school for ten years and letters of recommendation for PhD programs I graduated with a BS in physics in 2009, so it's coming up on ten years since I've been in academia. I have a great relationship with one professor, with whom I'm still in contact, and my old advisor would most likely also help me.

The problem is that most places I see want three letters, and I don't know of any other professors that'd likely remember me. I do, however, have about half a dozen former class mates. I have a friend doing a postdoc at Yale and another at Lawrence Livermore. I also have another friend who just finished her dissertation at Berkley.

I have a wide range of research experience, am published (I helped an experimentalist and got tacked on to the groups paper in phys rev), and have fair grades from a very challenging curriculum (e.g. general relativity, qft of a scalar field, theoretical techniques, intro to string theory), and am not worried about the subject GRE hell (I've done it before and scored in the 80%s once and 90%s the second time).

My problem is that usually one needs 3 letters. I currently work in tech, and could get a great letter from my department's boss, but the only time I do math there is when I make corrections to complex integrals an EE's whiteboard. Or when I'm bored and start calculating connecction coefficients for a metric or dervice generators for SU(n) n>2.

Any advice would be most appreciated!
From what you say it is not clear how your current job is related to the PhD you plan to study. But in general, excellent recommendation letter from your working place might be a good complement to two academic letters. At the end, your work did require technical / analytical skills, and those are the skills that will be useful in academia. Had you been a soccer player or dancer, this would have been a different story. Also, probably you can ask your boss to focus on some aspects that you think are important to emphasize (e.g., technical skills).