A lot of people around NC say the Blueberry is a really good yeilder. The Kush strains are really good yeilders as well. If yu do a little reading here and on some of the breeder sites, yu can get a fairly honest picture of the better yeilders. I like the info on the "legend seeds" website and "Greenlife seeds" website. But with any of them, the real measure of yeild and quality is gonna be proven with the TLC yu give them and grow methods yu use. good luck with it.
Even the highest yielding strain can produce poor quality buds unless all the variables are taken care of.
Advising what you are trying to medicate would be helpful, you wouldn't want to be taking a kick arse indica for depression or a stratospheric Sativa for hyperactivity.
From your user name I gather that you are in SLO California. . . I really like Blue Dream for a beginning grower. Also consistant good yielders that I've seen at the clubs and in various growrooms are Bubba Kush, AK47, and, Chem Dog. . .
I personally did really well with Sour Diesel too but I've seen some less than dense finished product from some decent growers too.
Highest yielding strain I've grown personally was Nirvana's Snow White. Huge, solid, dense colas. Pretty sticky, all indica buzz, great for beddy-by time and/or pain relief. Maybe not as strong as some of the more 'recent' indicas out today, but an easy grow and was a great yielding strain for me.