Website with OW Routes?
 

I'm looking for a resource (ideally like a Google Map) which contains a list of all OW destinations and that allows you to click on a given city and then see all the nonstop OW flights that originate from that destination and lists (or indicates with map lines) the cities to which the flights travel.

It can be pretty time consuming to look up the Wikipedia entry for every airport I'm interested in flying to/from and then check OW airlines under the "Airlines and Destinations" section. Thanks for any help you can offer!

Here you go - oneworld Online Timetable

Reached via oneworld.com --> flight schedules --> Where we fly --> interactive network map

Have you tried the Oneworld network map tool:
oneworld Online Timetable

Beware: The oneworld maps sometimes show routes that turn out not to exist when you try to actually book them.

The routes shown on the map do exist. The map however, does not account for routes that are seasonal or less then daily. Thus the route might not be operating on the day you try to book.

It also shows routes that are yet to commence - for example QF's to be PER-LHR non-stop