New maps?

[SoulEvolution]

I have played L4D for some time now, and not that i am becoming bored of the game, but i want some new maps!
will steam release any new maps? do they have any now?
i havent spent much time looking, but i have noticed that there are some third party maps available for download when i search for servers. I am kind of scared to download these, because im afraid of getting some kind of virus, its my dads computer that has L4D on it, and if i get a virus he will basically ban me from the computer, and i wont be able to play anymore! that will make me pretty sad :(
can anyone tell me about any downloadable content that i should not be afraid of?

[Obsidian]

Valve is releasing a new official map called Crash Course some time this month. As far as third party maps I haven't had any problems with them besides being completely unpolished. Does your dad have an anti-virus program installed?

[SoulEvolution]

he has some panda software installed, but he uses it for stock trading, and if something happened to that computer, he would basically destroy me lol
im pretty sure his computer would be fine, but he is strict about this kind of stuff, and he uses that computer every day all day until like 8pm, so if something bad happneed to it, he would destroy me
he said that i could put another hard drive on it, and get my own OS, but i dont want to spend 80 dollars on XP Pro, because i am a poor kid :P

[Mochan]

Panda AV is horrible tell your dad to switch to something else.

Of all the maps I got for L4D so far this is the best one:
http://www.l4dmaps.com/details.php?file=33

[SoulEvolution]

he paid for it though, and everybody has their own opinions about programs, some people like AVG, some people hate it, i dont know what to say about panda, but i would rather not get him pissed off at me for trying to know more than him

[SoulEvolution]

should i be at all scared to download maps from l4dmaps.com?