...Regarding these, though: Duskblade is basically a warrior-mage straight from level 1, and is very strong, even brokenly so in some cases. Beguiler is a rogue-mage sort who gets some minor fighting tricks, but focuses on skills and spellcasting (and only has mind-affecting spells and such). Hexblade is an arcane, evilish equivalent to the Ranger or Paladin, in that they are primarily warriors who gain minor arcane spellcasting at 4th-level onward, and use some curse-related class features to weaken enemies in battle, but Hexblades are kinda weak.
Warlocks just blast stuff a lot with an infinitely-reuseable but kind of weak Eldritch Blast, and develop a handful of similarly-reuseable Invocations for various tricks, attacks, and special abilities. Warmages are essentially similar to Sorcerers but heavily focused on Evocation spells and general offense, able to cast arcane spells in armor to some extent, and with a bit more combat ability for their limited range of capabilities (all they do is blast stuff with various spells, and hit stuff with weapons, and they're not so good at the latter). Bards you know about cuz they're in the Player's Handbook. Battle Sorcerers are a variant on Sorcerers that get slightly better HP, attack bonus, and such, but fewer spells and a focus on combat spells...