Finding Direct Flights to A Destination
 

Wondering if there is there a quick way to find out which airports offer direct flights to a destination. Say I wanted to find which airports have direct flights to San Jose Costa Rica....

All the options should be available here. Make sure you mean direct and not non-stop.
http://matrix.itasoftware.com/

Good point.

OP, did you mean "non-stop?"

"Direct" in airline parlance means that you can have an intermediate stop, including possibly a change in planes... as long as both flights have the same flight number.

There are a number of downsides to direct flights. They can cost more, you get less FF credit, and if there is a change in planes, you can miss your connection. Yes, your connecting flight DL xyx can depart while you are arriving on DL xyz. And, you do not get upgraded on any segment unless you are upgraded on both segments of a direct flight.

Direct flights are a marketing trick that only benefits the airline.

I like the wikipedia view - http://en.wikipedia.org/wiki/Juan_Sa...d_destinations

Many airport websites list all the other airports that have nonstop service to/from the location.

For Delta operated flights, you can use the following link:
http://delta.innosked.com/(S(ntkq2v5...)/Default.aspx
Here, you can select San Jose as the originating city and will see flights to Atlanta, Los Angeles, Minneapolis, and New York

+1

I always use the Wikipedia articles on the airport in question. I went this route for my flight to Santa Fe this past weekend when deciding whether to fly to SAF with a connection (not on Delta), or to opt for a nonstop Delta flight to ABQ with a drive.

(FWIW, I chose a direct flight on Delta ATL-ABQ + a $10/day ($18 with tax) car rental rather than a connection on AA or UA via Denver or Dallas.)

What do you put in for the "departing from?" Can you search for non-stop?

Yes, you will have to explore on your own to find the options. For example, departing from can be "nearby" 2000 miles from MCI or wherever. Near the bottom is a limit on stop but if you really want direct then there is a routing code for that.

If you want to search non-stop flights, from a particular airport, you can search here. Enter your home airport and the month you want to fly and it will show you all non-stop flights plus the airlines that offer them.
http://www.kayak.com/direct

As the OP wants directs TO a destination, I take this as them looking for where flights landing at a particular airport are coming from, rather than to where they're going. Irrespective of interpretation, I often use airport websites when looking for direct flight options.

http://lmgtfy.com/?q=direct+flights+from+SJO
I'm not being passive aggressive with the LMGTFY... it's the only way I know to start researching flights to/from a location. You have to type in direct flights FROM SJO. From there I assume they fly the other way as well.
I figured it out last year while trying to find reward flights with skymiles to Sri Lanka.

For Delta it's ATL, LAX, JFK, MSP.

+2 -- Wikipedia is the best for this.