How long has this been happening? It's possible that the servers were just down when you tried; it happens fairly often (just now happened to me). If you would like to update AVG Anti-Virus manually, update just like you normally would. But this time, click on Folder instead of Internet and navigate to the .bin file you downloaded.
As for Anti-Spyware...you might just have to keep trying until you get through. As far as I know, they don't have manual update downloads for this program; only Anti-Virus.