Can't sign in to app store

OK, newbie here. I click on Store but where do I sign in?

OK, I was able to go into my account (well, it's my husband's account - I have one too, but his seemed to be working on line) and updated one-click shopping. So I guess I can get in there.

OK, I created a new account and was able to buy something from iTunes. It shows in the iTunes library but it doesn't show on the iPod. Then I noticed that the games on the store were just iPhone or iPad. Did I download the wrong thing? So I tried, once again, to buy the game (Angry Birds still) from the iPod and it says it can't connect to the iTunes store. So I tried buying Spy Mouse and it gave the same message and then the game was there. So I went to try Angry Birds again and it said it was downloaded. Where? It doesn't show under Game Center. Well Spy Mouse doesn't either; it's just on the second page. I tried to log on to Game Center with one of my million IDs and it refuses to change. We bought this mostly because my husband needed a new mp3 player and he did get that working, but it would be nice to get the other things to work.

Because I was being sarcastic. Right now I have three. I can't get into the itunes store with any of them. The internet works.

Sorry, frustration brings out sarcasm. Anyway, I've done all those things. And some things work. I downloaded the barcode reader to the computer, plugged in the iPod and it moved right over. I downloaded Tips and Tricks for iPod Touch - same thing. Downloaded Angry Birds HD for iPad thinking/hoping that I had downloaded AB for iPhone and that's why it didn't work. It shows in my iTunes library but it's not showing anywhere on the iPod. Maybe I need to read up more on gamecenter. But everything that did move over just got its own spot on the desktop.