Yes, Rakshasa player characters are supported! ...sort of.
The Monster Manual (page 212) has the typical monster manual "RAKSHASA AS CHARACTERS" racial stats block: they start play as level 14 characters (7HD and a +7 LA) with an effective seven levels of sorcerer built into the character (future class levels of sorcerer stack with the racial levels). However, it's important to remember that many of the "_ AS CHARACTERS" stat blocks are more suited for the DM's use in making NPCs; while technically they're viable as player characters, it may not be a satisfactory experience. The DMG1 (page 172) notes that "most monsters are not suitable as PCs" even when joining other characters who are at their effective level after adjustments. Whether the Rakshasa is overpowered (providing seven levels of caster and some sweet monster features) or underpowered (half-level casting of a non-optimal casting class and some monster features which may not compensate) I leave as an exercise for the individual group, but it is wonky.
With that in mind we can now look at the 3.0 Savage Species book (page 191). It contains a "racial class" gimmick which lets you start as a level 1 Rakshasa with minimal features and slowly level up as a Rakshasa. At level 14 you become a full-fledged Rakshasa and from 15 on you start taking regular classes.
Although Savage Species is 3.0, it was never re-released for 3.5--only errata'd, and very minorly at that--and technically that means Wizards considers the book's contents (with errata) are considered 3.5-compliant. In practice, the SS Rakshasa is somewhat less balanced and I'd suggest anyone using it to work with their GM to tweak its features to realign them with the 3.5 version of the creature. For example, 3.5 Rakshasa have high spell resistance while 3.0 Rakshasa get immunity to spells of incrementally higher levels. Spell immunity is a messy business and overall I find the spell resistance version is easier and more balanced.