Blood tests without a doctor’s order are available at LEF.org. You would need to have the blood drawn at a LabCorp office near you, if there is one. I use them a good bit. The prices are reasonable, and the tests are the same tests, at the same lab, as your doctor would order. But it takes about three weeks to get them done - they mail you the requisition, you take it to LabCorp, then they mail you the results. Snail mail.
I’m not sold on saliva tests. I tried them several years ago, and got wildly inconsistent results over time.
You need total and free testosterone, or at least free testosterone, and estradiol.
Formula1, I’d suggest you find a site such as Dr. John’s forums, or the Yahoo Group hypogonadism2, and post your test results, You’ll get some pretty-well-informed opinions as to what they mean. But if everything collapsed six years ago, you need to try to pin down what happened to trigger that. Did you start new medications about that time? Change your diet significantly? Stop exercising? Gain a lot of weight?
Finding a doctor who will work with you on this stuff can be very difficult.