I am a techno fanatic so here we go...
Progressive Hardhouse/techno: DJ Irene or any of the HardHouse compilations
Breaks/Beats: The Prodigy, The Crystal Method, The Chemical Brothers, Fatboy Slim, Propellarheads, Leftfield, Orbital
Hardcare: Sy & Unknown, Scott Brown (get Hardwired, it rocks), 3 Steps Ahead, Force & Styles, Ethos/Kaos
Drum and Bass/DnB: Dieselboy, DJ Dara, Gridlock, Total Science, Orion, any This Is DnB compilations
Hard Techno: Warp Brothers, Voodoo & Serano, Public Domain, Andy Hunter, Overseer, DJ Digress, DJ Mellow-D, Sunbeam, Talla 2xlc, Junkie XL, Keoki, Plastic Boy, The Potatoeheads
Trance: Tiesto, ATB, Ferry Corsten, Markus Schulz, Fragma, BT, 4 Strings, Armand Van Helden, Armin Van Buuren, Blank and Jones, Cosmic Gate, Daft Punk (tech/trance), Darude
Chill: DJ Zephyr, Massive Attack, Underworld, Royksopp, Fischerspooner, Chill Anthems, Banco de Gaia, Faithless, The Flunk, Groove Armada, Ladytron, Thievery Corp., Moby
Tripno: Infected Mushroom, Hallucinogen
Recommended Albums: Hardwired (Scott Brown), Fat of the Land (Prodigy), Warp Factor (Warp Brothers), Cold Blood (Voodoo and Serano), Phonosynthesis (DJ Irene)... start with those for hard good stuff, and let me know if you want more!