I've only made a few attempts at this with some success. I also used deep sky stacker. I used a standard ballhead tripod, a canon 7D, and a 17-55mm f/2.8.
There is a little more to it then just stacking the exposures taken (light frames).
Steps taken:
I took 20 exposures @ f/2.8, 15/sec, ISO 1600, 17mm (even this gave me a small amount of trail on my stars). IMMEDIATELY after I took 15 "dark frames". To do this you leave all of your settings the same, put the lens cap on, then take your exposures. The point of the dark frames is that it essentially takes a picture of the camera noise, hot pixels/dead pixels. Deep Sky Tracker will compile those into one dark frame to subtract that information from your set of light frames. It's important to do it right after your exposures while your sensor is still the same temperature, thus the noise level is the same.
When using your stationary tripod, you would not be able to take 500+ exposures, and here's why: the only option you have is for DSS to locate all the stars in your frame (even tells you how many) and align them. Ultimately you have less stars than in a single image because of how the stars drift. If there are stars that drif out of your frame, and new ones drifting in, it won't stack those and cuts them out of your final image. SO the fewer frames you can get away with, the better for that reason. What you'll notice in the final product is that the stars are stacked, but any forground will have moved instead. Thus the need to make a composite image.. one of the stacked stars, then adding in the foreground, usually by using layer masks in Photoshop.
From what I've learned in my attempts, I'm almost positive the first image was done with a wide angle lens using a tracking tripod. If it had been stationary, after taking his exposures the milky way would have moved all the way accross his frame, if not completely off of it and he would have been left with little to no stars DSS would recognize as being the same, and stackable.
SO it can be done with a standard tripod. Location is the key. Get away from any light polution ( I mean ALL the way away), check a moon phase calendar and plan it for a night that there will not be a moon in the sky, get as wide as you can, with the aperture as wide open as possible, and hike up your ISO as high as is practical. My next attempt will be ISO 3200, maybe 6400. There is some math you can use to judge how long you can expose for without creating star trails. I didn't use it. I simply took a test exposure then zoomed in on the preview, adjusting until I found an acceptable setting.
Give it a shot and have fun. :) oh, and don't be alarmed when you see red pixels in your display after shooting for a while. You can spend six grand on a Canon 1Ds MKIII and still have dead pixels. It's unavoidable. ;)
I'm no expert and I certainly haven't figured it out completely. I'm hoping someone will reply with some suggestions for me as well.
-Rocco
EDIT: be sure turn high ISO and long exposure noise reduction OFF. It's unecessary using this method.. and takes just as much time to apply it as it does to take the exposure. The less time in between exposures, the less star drift there will be.
Also worth noting.. DeepSkyStacker is a free program.