While gay folks are not included as a "protected class", one would do well to avoid any semblance of STEERING. (It's on the Google.)
Madison is, overall, pretty gay-friendly but it would be difficult to draw a RED LINE around one area and proclaim it to be the The Castro of our city.
You can hardly swing a dead cat around here without smacking a gay realtor in the...well, without hitting a gay realtor.
As the previous answer suggests this is not a conversation that can be had over the internet.
It is a very personal conversation that may be best shared after selecting your Realtor of choice.
Madison is a very Gay friendly community and that includes a wide selection of Gay friendly Realtors.
If would be as well to interview a couple and find one that appeals to you, and can answer your questions.
I wish you well in your home search.