Ok, I'll try to do a simple skeleton for a Warlock build. I'll assume Human, though you really can be any race. Able Learner and some of the skills won't work without Human or human blood, though.
Hexhammer (32 point buy)
Human Warlock 10
Str 10, Dex 16 (-->18 from levels 4, 8), Con 14, Int 14, Wis 10, Cha 14
Eldritch Blast +11 (60/250 ft ranged touch, 5d6 untyped damage)
Class: Eldritch Blast 5d6, Detect Magic (at will), DR 2 / cold iron, Decieve Item (can always take 10 on UMD), Fiendish Resilience (1/day free action, fast healing 1 for 2 min.), Energy Resistance 5 (Fire and Cold)
Skills:
Bluff +15 (13 ranks)
Concentration +15 (13 ranks)
Hide +10 (6 ranks)
Know Arcana +7 (5 ranks)
Move Silently +10 (6 ranks)
Spellcraft +6 (2 ranks)
Tumble +10 (6 ranks)
UMD +15 (13 ranks)
Feats: Able Learner, Point Blank Shot, Precise Shot, Maximize Spell-like Ability (Eldritch Blast). If you can take a flaw or two, you could pick up some fey heritage feats. Alternatively from Maximize SLA, you could use the last feat to learn another least invocation.
Invocations (3 of each level, my choices with *):
Least: Devil's Sight, Darkness, See the Unseen*, Baleful Utterance*, Breath of the Night, Frightful Blast, Eldritch Spear*, Spiderwalk
Lesser: Fell Flight*, Walk Unseen*, Flee the Scene*, Hungry Darkness, Charm
Gear: Load up on scrolls and wands to take advantage of your massive UMD check score. You can automatically make DC 25, enough for any wand and up to CL 5 (ie, 3rd level) scrolls. If you use Magic Item Compendium, look for Warlock items in there. Boosting stats, AC, etc... is always useful.
http://www.crystalkeep.com/d20/rules/DnD3.5Index-Classes-Base.pdf (p. 165)
http://www.crystalkeep.com/d20/rules/DnD3.5Index-Invocations-Warlock.pdf