Here's a partial list. Lots of outsider forms but maybe you'll find something useful.
Forms
Alter self
Azer (+6 na)
Dwarf ancestor (+18 na)
Quasit (flight, dex damage poison, toad wolf form)
Imp (flight)
Arrow hawk (flight 2d6 electricity bolt)
Triton (swim speed)
Xill (plane walk)
Xorn (burrow)
Polymorph
3 hd. Ravid (animate objects, 2d10 positive energy vs undead)
4 hd. Spider eater (paralysis poison, flight, freedom of movement)
5 hd. Ethereal filcher (ethereal jaunt)
5 hd. Rust monster
6 hd. Achaerai (insanity cloud)
6 hd. Barghest (le magic aligned weapons, consume body ability prevents raising)
6 hd. Bearded devil (infernal wound, beard, rage
6 hd. Bralani (tongues)
6 hd. Formian (dominate monster)
6 hd. Nightmare (astral projection, etherealness, flight)
6 hd. Succubus (negative level/suggestion, tongues, ce aligned weapons, flight)
7 hd. Avoral (healing, true sight, big dex and na, flight)
7 hd. Babau (sneak attack, acid skin)
7 hd. Djinni (plane shift others, telepathy)
7 hd. Lammasu (pounce, magic circle against evil)
8 hd. Aboleth (enslave, slime, mucus cloud)
8 hd. Hellcat (invisibility, pounce)
8 hd. Invisible stalker (tracking)
9 hd. Erinyes (true seeing, entangle)
9 hd. Will o' wisp (flight, magic immunity, invisibility)
10 hd. bone devil (str poison)
10 hd. Ghaele (cg aligned weapons)
10 hd. Retriever (blasting/petrify eye ray's)
11 hd. Beholder (win)
12 hd. Bebilith (con damage poison, web, plane shift self)
12 hd. Leonal (roar 3/day=holy word)
14 hd. Sarrukh (win)
ETA: check out this link for more.
http://www.minmaxboards.com/index.php?topic=9399