List of (almost) all way to change form!

[Metastachydium]

Two more (old favourites of mine):
1. Mountebank^DComp; gets Infernal Guise (Sp) at level 4, which is essentially Alter Self for up to 1/2 mountebank level + CHA modifier number of days;
2. Mountebank^CS; gets an Alter Ego (Sp) at levels 3, 6 and 9, which is essentially Altrer Self at will, but the mountebank can only assume one specific form with each instance, ending up with four forms they can switch between at will at level 9.

Edit: Deepwyrm drow and half-drow^DrM have Disguise Self as a 1/day SLA; if the lesser version is used for drow, both are LA +0.
Edit (again): The Tainted One^RoF template (LA +2) gives Polymorph (into viper forms only) as a 3/day SLA; Yuan-ti can do the same at-will, but it comes with alot of RHD.
Edit (again): Slyths^Und (LA +2, no RHD) have an Alternate Form (Su) ability. They can turn into an amorphous puddle with it.