Mid-40s? Oh man. Hopefully he meant a very fertile woman in her mid-40s. How old are you, if you don't mind me asking?
I've not tried DHEA yet, but I'm all for anything that might perk up my poor old eggs! I have to do my research carefully before trying anything new, though, because I'm hypothyroid and certain things can interact with my meds. My situation is a bit complicated because, in addition to having elderly eggs, I have immune and blood clotting issues which may be at least partially responsible for my recurrent miscarriages.
I recently learned about CCRM's protocol for PCOS/aging eggs and have added a modified version of it to my regiment. The original list includes melatonin, but that's supposed to be more for the PCOS people (which I'm not) and I've heard it can interfere with ovulation so it's maybe not so good to take unless you're planning a stimulated cycle. Anyway, this is what I'm taking at the moment:
CoQ10 - 400 mg (200 mg, 2x daily)
Ubiquitol - 200 mg (100 mg, 2x daily)
L-argnine - 2000 mg (1000 mg, 2x daily)
Myo-inositol 4 mg (2 mg, 2x daily)
Omega-3 - 840 mg
Vitamin C - 500 mg
Vitamin E - 200 mg
Prenatal vitamin
Vitamin B12 (P-5-P) 25 mg
Vitamin B6 (methylcobalamin) 500 mcg
Metafolin (activated version of folic acid) 800 mcg
The last three things on the list are activated forms of B-vitamin supplements that are supposed to help for certain immune-related issues. Also, some of the things on that list - like the myo-inositol - target insulin sensitivity, which is, again, more for the PCOS peeps, but I figure it couldn't hurt because I have a strong family history of diabetes/insulin resistance and could do with some insurance against that sort of thing.
Cripes, those supplements are expensive!

May need a second job to pay for my new pill habit. Also, I couldn't find the myo-inositol in any shops where I live, so had to order it online.
Thanks for the info about black cohash. Looks like it's supposed to help with ovulation? I'd never heard of it before, but funnily enough, I just saw scads of it at Whole Foods today. Must be pretty popular. I don't think ovulation is so much of a problem for me, though...I get pregnant, just can't make those babies stick!
I've heard Royal Jelly helps, but I haven't been able to find any legit scientific studies backing it up. Do you take Evening Primrose Oil throughout your cycle, or just from Day 1 to ovulation? This month was my first cycle on Clomid, and I noticed I didn't get any EWCM, so I might start taking it next cycle.
You're lucky your guy is willing to take supplements. My DH just looks at me like I'm crazy when I suggest it!