Tomorrow is the last day to register to vote in Maryland's Sept. 13 primary elections. You can learn where to register by calling Sundial, The Baltimore Sun's telephone information service.

For most users, the number to dial is (410) 783-1800. But in Anne Arundel County, call 268-7736; in Harford County, 836-5028; in Carroll County, 848-0338.

Then, using a Touch-Tone phone, punch in the appropriate four-digit code after you hear the greeting to get information about where you live:

* Anne Arundel -- 6181

* Baltimore -- 6182

* Baltimore County -- 6183

* Carroll County -- 6184

* Harford County -- 6185

* Howard County -- 6186