Easy way to make frequent travel plans?

I work for a company that frequently travels to a number of cities nationwide. Is there a search engine type website that allows me to find one airline that travels to each of my destinations? I am trying to find an easier and maybe more cost-effective way of booking flights without using an orbitz-like website and possibly going directly through one airline. But I wasn't sure if there was an easier way short of looking up each airline and typing in each city.

Also, is there a way to have an auto-update of available flights from a specific airline?

Since you are booking travel for a company, I highly recommend taking a look at different travel providers' corporate sections (e.g. Expedia Corporate Travel, JetBlue Corporate Travel, Delta SkyBonus). They specialize in exactly what you're looking for. Companies like the ones already mentioned, as well as most airlines, offer these programs.

If that's not what you're looking for, I know that if you sign up for Delta SkyMiles, when you create a profile, you can add your most frequent trips (routes), so you don't have to go searching - you just click on the trip, select the dates, and flights come up (you don't need to type in the cities each time). As for a single airline that flies to all of your destinations, Delta also works. They fly to many destinations, and with the SkyTeam airline alliance, they have even more destinations (code-share). It's really worth taking a look at.

My father's company uses Expedia Corporate, and from what he tells me, they're really good at this thing. Good luck! http://answers.yahoo.com/question/accuse_write?qid=20070827141004AAcIg7N&kid=EMQnCWfpWTCg8IZmL9jOUl8A_Hij.183f6g7ebfSJshWqx8RQJMn&s=comm&date=2007-08-29+20%3A01%3A53&.crumb=

There is a search engine called Kayak.com that will search about 300 airlines for prices and available tickets. You do have to put in your city pairs, but the also offer a fare watcher free service where you can put in 6 different city pairs and get emailed when there are deals on these flights. It is very handy!