Most straightforward way to buy T-bills?

[tenders]

Not really. 10-year Treasury notes are yielding 3.00%. Of course it's not a riskless 3%, nor is it costless to trade in and out of them, but if he's right about rates not going up soon he can buy those hold them for as long as he thinks rates will be flat and get the 3% yield.

30-year Treasury bills are yielding almost 4%.

http://www.ustreas.gov/offices/domestic-...ield.shtml