Anybody got any tips for driving from New Haven to Philadelphia?

[KathyK]

Hi Everyone,

I'm driving from Connecticut to Philadelphia next Saturday afternoon
to see They Might Be Giants perform at the TLA.  I haven't been to
Philadelphia before and driving around unfamilar places scares me. 
The idea of driving around large, unfamilar cities in the dark makes
me feel panicky.

So, before I flip out and do a pre-trip drive down there, using up
time and gas, does anyone have any advice about the drive(I've already
been advised not to drive through New York City, which I wasn't
planning on doing if I could help it, anyway)?  Most importantly, does
anybody have any helpful tips for driving and parking in Philadelphia
on a Saturday night on a holiday weekend?  Various websites list
different lots and street parking nearby but what are the chances a
50-space parking lot will have open spots?  Should I be looking for
some ginormous parking garage further away from the venue?  I really
don't want to spend a lot of time driving around the city trying to
find parking.  I want to get to the venue as soon as I can.  How easy 
is it to get around the area on foot?  Will I feel really freaked out 
walking back to my car at midnight or later?

Thanks for any and all help!

KathyK, who would leave early in the morning on Saturday if she could
to avoid all the worry but has to work until 3