What you need:
1. Your old residency card
2. Your passport (you need to enter your passport number on the form)
3. If you are married to a dominican, you need to know your spouse's cedula number, although I got my new card without this information.
4. a ballpoint pen
Where to go:
This is done at the main offices of Migracion located in Santo Domingo, at the intersection of Ave George Washington and Calle Heroes de Luperon. (This is the first intersection with a stoplight west of Ave Enrique Jiminez Moya (the bottom end of Winston Churchill) and Ave George Washington (the Malecon). They are open from 8:00 am until 3:00 pm, BUT they will only accept your paperwork for residency renewal until 11:00 am.
There is a large parking lot located behind the building, or you can park along the street. Lots of guys trolling the parking lot to "help" you and "watch" your car while inside. Lots of others hanging around the entrance offering to "help you" with your work inside.
Entering the front entrance (facing the sea), you need to go into the right side offices. The other side is for Passports only.
Buy the application form ("Formulario para la renovacion de mi residencia") at Window #9 for RD$100. A good place to fill it out is at the large counter in Reception outside in the main entrance., as long as you go off to one side, and tell the girls behind the counter how pretty they are.
The form asks for your first and middle names, ("NOMBRES" = your first and middle names), your last name(s) - ("APELLIDOS" = last name(s),) each of your parents names, your Dominican address, your passport number, your country of citizenship *"NACIONALIDAD"), and if it applies -your dominican spouses name and cedula number, etc.
Fill it out, turn it back in at Window #9 along with your old Residency card. Take a seat and wait about 45 minutes for them to review it and give authorization.
They will then call your name and you will pay the RD $2500 fee (and RD$2000 more for VIP service if you want fast service) plus any late fees if you are late in renewal, at Window #9. They will give you a numbered ticket and your paperwork.
You then then take the approved form and your receipt to Window #3. After about another 45 minutes they will call your ticket number for the photos. They usually call 3 numbers at the same time.
Go into the central hallway leading away from the center of the building and go to the first door on the left in this hallway. There is someone at this doorway who will direct you down a short hallway to wait in the hallway outside of the last door on the right side. If you don't speak Spanish, just hold all of your paperwork in front of you and they will point the way.
Queue up in the short hallway, and they will call "proximo" from the small room. They will take a front and side view, and then you go back out into the waiting area and take a seat (pet peeve = instead of hanging out in front of the hallway and gumming up the way for people to pass. There are a lot of people coming and going, and it doesn't help anyone trying to get through if there are 50 people standing around in the way.) Your new residency card will be ready in about 30 minutes and they will call your name.
A gentleman will come out of the central hallway with the latest batch of cards and will start calling names to come and collect their cards. If it's been about 30 minutes and you don't speak Spanish, just walk up to this area when the guy comes out, he will see your face and match it to the card and hand it to you.
CHECK THE INFORMATION ON YOUR NEW CARD BEFORE YOU LEAVE. Sometimes they do screw it up, and it needs to be correct. They used to have a hard time with using only three names and not four, and get them out of order.
I came in at 8:45, and walked out at 11:25. About as efficient as they can make it I guess.
I renewed my residency two months before it was due for expiration, and had no problems. The only difference was that I lost the two valid months remaining. The residency is good for 2 years, but after you have had residency for 10 years, they give you the option of longer renewals.