i don't know the single b-sides BUT perhaps should have a look..
as for the discography:
1988 Ultramega OK
1989 Louder Than Love
1991 Badmotorfinger
1994 Superunknown
1996 Down on the Upside
i only knew about them from badmotorfinger on but you can start with the whole rest of the superunknown album if you want to start with the black hole sun album

i like most of these tracks, i guess especially my wave, fell on black days, head down, spoonman, day i tried to live, she likes surprises...
could check out badmotorfinger, another commercially successful album which i like better than superunknown.. it was my first

and still holds a special place in my heart.. jesus christ pose at lollapalooza.. yikes
on wiki i ran across some badmotorfinger b-sides loobie probably knows well:
The album's singles featured eleven B-sides from the Badmotorfinger recording sessions that weren't included on the album, "Stray Cat Blues", "Into the Void (Sealth)", "Cold Bitch", "I Can't Give You Anything", "Girl U Want", "Show Me", "I Don't Care About You", "Can You See Me", "Homicidal Suicidal", "Touch Me", and "She's a Politician".
also check out temple of the dog ... maybe the 'singles' soundtrack (maybe not in terms of the soundgarden contribution actually) and.. straying a little outside the soundgarden boundaries... dare i say it... mother love bone...