Since I'm not at home, I won't click them to check out where they lead, but just as a note, tinyurl.com and bit.ly are both url shortener sites. They are getting to be used more and more often so that a long link (M$'s site links are often quite long as an example) can be posted without taking much space. You'll see the same kinds of links on many Facebook app posts, as another example.
Personally, though, I'd prefer people post a link using the url tags and just labeling it something short so that a mouseover of the link will show the site address.
Just to check regarding your sounds... do you have sound enabled in mIRC's options?
As far as sounds in Windows 7, I know they work fine in 32bit on my system and I know people using 64bit who have sounds. So it's likely some configuration there or driver issue that's causing problems.
