we still want to meet guys too and it wouldn't make sense that the places/situations differ from guys. some of these examples are how guys would talk to me or would meet me even if it wasn't for a date, even though you did direct it to guys only i can still give a bit of insight on this ithink.
so, if you don't have friends who you meet people through, i'd say places where you share similar interests or just something in common. for example, at concerts, through clubs (could be anything like sports, art, reading, etc), in classes (taking the same courses would count as something in common even if it's not an interest).
there is the possibility of approaching strangers in more "neutral" (i mean, where there isn't something you would clearly have in common) public places, like grocery stores, on the bus, etc. but when i've been approached in those situations i have nothing to judge the guy on, particularly since they don't even ask about interests that much and just get to the point, so i'm much much less inclined to want to date or get to know them.
plenty of SA guys date and get into relationships.
you can find countless examples on this site.
with anyone, it takes enough confidence and initiative to at least express interest and to maintain the relationship (even if you aren't the person who initiates the relationship, you still need those qualities to keep it going as i know from experience). that doesn't mean you have to be extroverted, be so confident you love everything about yourself, or even have achievements to prove to the person that you are better than others, etc.
just enough that will get you to push yourself to do it and that can help you handle rejection in a decent way.
the internet is a good place as well. for both relationships i have had, i met them through random forums (not dating sites, it developed more naturally) and they both ended up having SA.