Tonberry Crunch
Everyone that I've encountered that use Veigar use him far better than me D:
(All two of them) Are you starting with baleful? because you'll need all of that last hitting for later on in the round. it's not unusual for a viegar to farm up to about 100 Ap with just balefuls, not to mention champion kills with baleful net you 5 ap.
i'd start with baleful, event horrizon, baleful and then dark matter.
you can mid or lane with someone, either way works, but i find laning to be easier to get used to.
ive found it easiest to start with a meki pendant and two pots, then go into tear of the goddess. you REALLY want tear due to the mana pool increase, since your running your Q almost constantly.
for magic pen. sorc boots should be all you need, hope that helps.