I tried the other day to get my DM let me be a Shade (a template from page 314 of the Forgotten Realms Campaign Setting, a 3.0 book) for a new campaign. He looked at its abilities and said there was no way that it should be just LA +4, and I agree. I would like to know how to update this 3.0 edition template to 3.5e so it they can be used without unbalancing the game.
I wrote about this for Dragon magazine!
The shade has a 3.5 update in Dragon #322 (August 2004). It's divided into a Savage Species style progression for the article, but is otherwise functionally identical to the version in both the Forgotten Realms Campaign Setting (2001) and Races of Faerun (2003), except for the following changes:
However, the shade's ability set is extremely good, and I'd think very carefully before allowing it as a PC race. It gets flat bonuses to saving throws, skills, attack, damage and AC that ease the penalty of level adjustment considerably. Fast healing lets him heal to full between combats, for free. His hiding becomes exceptional. In dungeon campaigns, you rarely encounter daylight, so the shade rarely loses his powers.
That said, if you often fight encounters in bright light so that the shade can't use his powers in every encounter, I actually consider it balanced at +4. The invisibility ability consumes a standard action so it's not as good as plain sneaking, and what you gain in defensive abilities (saving throws, AC, spell resistance and improved hiding) you lose in hit points and class abilities. The control light and darkness-reliant abilities hinder allies who can't see through magical darkness.
Generally, see the other question What are the major differences between D&D 3.0 and D&D 3.5 especially the first answer, which has links to the conversion docs.
For this template in particular, it's a little complicated. The FRCS errata document adjusted the template's LA to +5. There's a newer version as an actual PC race that's LA +4 in Races of Faerun. The D&D Wiki has a fan 3.5'ed version with various LAs noted.
Also see the Shade wikipedia article for some Dragon mags it's appeared in that might help.