I'd definitely recommend doing it yourself. It's actually rather easy as long as you follow the instructions or some basic rules...and the tools aren't that expensive - probably around the cost of one cleaning at a shop, and you can use them many more times.
First step to cleaning your sensor is to buy a rocket blower if you don't already have one. Any bulb-type blower that has a dust gasket on the intake will do. This tends to work about 90% of the time with sensor cleaning, often you need nothing more! You put your camera in cleaning mode in the menu, which flip the mirror out of the way, take the lens off, hold the camera with the opening facing down, then insert the blower into the opening without touching the sensor and squeeze the bulb quickly and strongly several times to jet out any dust.
If that fails to fully clean your sensor, the next most convenient tool that will work 98% of the time is to get a quality sensor brush. These are very soft bristles that are slightly charged and will pick up dust quite effectively with a gentle stroke across the sensor face.
If after the bulb blower and sensor brush, you still have something on the sensor, then you can go with the wet swab method. Sensor swabs are moistened on one end with a cleaning fluid (there are two types, one for standard and one for coated sensors...make sure you get the right one!!), then wiped across the sensor first on the wet side, then on the dry side. This will solve your sensor cleaning issues 99.8% of the time.
The bulb blowers go for between $20-70 or so, depending on which you get. The sensor brushes are usually no more than $5-10. And the swabs and cleaning fluid might set you back $25 or so. If you get a bulb blower on the cheap side, it will likely take care of your dust issues by itself, at around $20-30. Even with the brush and swabs, you can have a full, comprehensive cleaning kit for $50-60 total.