alrighty, letscook, i'm a vet, and i don't work in private practice at all, so i'm not getting any $ to say this. here's my 2 cents:
1. do NOT bathe your pets in borax. works pretty well as an environmental treatment, but its best use is for poofing into the walls (example: take off the switchplate covers, and tump a little down in there) to control roaches and ants that live in between the walls of the house. don't be dusting your pets, because them eating borax is not a good thing. you could dust your dog's bed with borax and then vacuum it all up later, but hot water & soap is just as effective, so why not toss the bedding in the washing machine and avoid the mess?
2. as others have mentioned, flea collars are pretty much crap. the only time to bother with a collar is if you DON'T already have fleas on the pet, or in the house or yard, AND you can't get a source of something better. they work by releasing insecticide that coats your pet's hair, so they take a couple of days to start working completely, and they'll also be used up quicker than you think they will. better stuff is available, so basically, don't bother.
3. flea spray, likewise, pretty much crap. the only way for this to work is if you spray all the pets in the house on the same day that you spread insecticide over the yard and bomb the house. repeat in 2 weeks, repeat 2 more after that. the point here being that fleas aren't ONLY on the pet, they're in the grass and the carpet and the dog's bed, and this is a life cycle just as complex & ongoing as lions hunting zebras on the serengetti, so if you just kill off some of the zebras, another herd will move in soon enough.
4. bathing the dog is far more effective than flea spray (at least you know you treated the whole dog), but at most, flea shampoo only has a week or so of residual activity. meaning that after that week or so, the shampoo's chemicals don't have any more bug-killing powers. don't forget you MUST treat the environment (house, yard), or the fleas will just jump right back on.
5. which brings us to what you should actually do. frontline, frontline, frontline. some of my colleagues will reccomend revolution instead (covers heartworms as well), but frontline is more powerful and longer-lasting, and it's what i use on my dog, so there you go. total solution = give dog a bath, and wash the bedding the same day. 3 days later (so dog is totally dry, and his skin oils have normalized over the hair coat), put that dab of revolution in between his shoulder blades. it's kind of oily in that spot, and lots of dogs want to go rub their now weird-feeling back in the grass, but don't let 'em. that oily spot will disappear in a couple of days, and then it's been absorbed into the skin, making it work even if you occasionally have to bathe the dog (it doesn't wash off easily at all). the package is labelled that you need to re-apply every month, but i get a good 2 months' worth out of each tube of this stuff. since frontline is so effective, you don't HAVE to treat the house/yard at the same time, though of course, if the fleas are biting YOU too, it'll help you keep your sanity if you do.
the problem with all the natural remedies is that it's totally unregulated. no way to tell if your brewer's yeast is live or dead in the bottle, your citronella oil might be real citronella or just lemony-scented, etc etc, which is probably why people report such varying results.
good luck!!