Antivirus and Windows 8

I'll be building my fist PC tomorrow and had two quick software questions. 

1) Is there a good but free antivirus software out there? I don't want anything that's a pain to get around when I don't particularly need it, just something to protect my computer just in case I download something with a virus or go to a bad website. 

2) Best and cheapest way to get Windows 8. I don't want to order the actual disk online because I'll be ready to start building tomorrow. I won't have an optical drive on my PC and the only tutorial videos I've found using a USB drive require the disk for Windows 8, is there any cheap solution to this that can just be downloaded and then transfered to the USB drive? I'm not inferring for it to be illegal, I just don't want to go to Bestbuy and drop $120 on the disk.  

Thank you for your time. 

1: Free anti virus, there are alot of decent free ones, i personaly use Avira Antivir. it works great for me.

Others: AVG Free, Avast free. and some more. just try which suits you the best.

2: You have to make a usb stick bootable, using Disk part on a diffrent pc, there are alot of tutorials to find about that.. then you need to download a windows 8 iso somewhere, and offcourse purchase a key.

+1 on Avast!