I personally started attending conventions back in 2004 and have to this day attended 20 (smaller, theme-based) conventions and 5 signing events (or larger, general events as I refer to them further down). For those interested, you can check my website for an overview of what events I've attended and who I've met, as well as checking out photos from the events and autographs I have collected
So, with that in mind, what is important to know?
Now, many would slag this off because of the price tag and call it riddiculously expencive, but then ask yourself this; how much money are people willing to shell out for a single concert with a band/solo artist they really want to see. If it's someone particularily known, you can bet the price tag for one single concert could easily rival the price tag of a convention ticket (and a concert lasts a couple of hours tops, while a convention lasts for days) - and people still travel, shell out on lodgings to go to those. And with concerts you have absolutely no guarantee you'll even get to meet that band/artist in person - in fact, you're almost guaranteed you won't - while a convention ticket (particularily a three-day entry ticket) will more or less include autographs and pretty much guarantee face to face encounters with the people you want to see. Just saying...
I hope this guide will be of help to some people, and I hope to see you guys at some future event, someday.