From Harper Lee's To Kill a Mockingbird, please provide a good quote for the courthouse location and its description.
If one were to draw a map of the town of Maycomb, it would have to be done from the the children's perspectives as they run around it. In order to get a complete idea, though, one would have to consult different sections of the story where Scout mentions the courthouse. The passages that contain references to the location and description of the courthouse are found below and listed in order as they appear in the book.
The first reference to the courthouse is in chapter one as Scout lays out the location of things as far as all of Maycomb county is concerned:
"Maycomb, some twenty miles east of Finch's Landing, was the county seat of Maycomb County. Atticus's office in the courthouse contained little more than a hat rack, a spittoon, a checkerboard and an unsullied Code of Alabama. . . Maycomb was an old town. . . In rainy weather the streets turned to red slop; grass grew on the sidewalks, the courthouse sagged in the square" (4 & 5).
Thus, the above passage places the courthouse in the main square. The next clue mentioned by Scout is the whereabouts of the Post Office:
". . . Jem and I raced each other up the sidewalk to meet Atticus coming home from work. . . It was our habit to run meet Atticus the moment we saw him round the post office corner in the distance" (28).
From this description, we learn the the Post Office is on a corner just down the road a little way from their house; so, they must live close to the main street and possibly the square.
Next, from reading about Jem vs. the mean Mrs. Dubose in chapter eleven, we discover the following:
". . . the business section of Maycomb drew us frequently up the street past the real property of Mrs. Henry Lafayette Dubose. It was impossible to go to town without passing her house unless we wished to walk a mile out of the way" (99).
"Jem . . . had concluded that it was cowardly to stop at Miss Rachel's front steps and wait, and had decreed that we must run as far as the post office corner each evening to meet Atticus coming from work" (100).
Based on the textual evidence provided, then, it seems that from Scout's house, the she would first pass by Miss Rachel's house, then Mrs. Dubose's, and finally stop at the Post Office which is on the corner of the main square; and the Post Office probably exists near or opposite of the courthouse in the main square.
For a description of the courthouse itself, there are two full paragraphs in chapter 16 that describe its architecture and the specific offices located therein. A sample of the second paragraph is found below:
"To reach the courtroom, on the second floor, one passed sundry sunless countycubbyholes: the tax assessor, the tax collector, the county clerk, the county solicitor, the circuit clerk, the judge of probate lived in cool dim hutches that smelled of decaying record books mingled with old damp cement and stale urine" (162-163).