Areas: downtown doesn't seem to be especially popular for providers, but it's a great area to stay and enjoy the city. Word is avoid the JW. Several other places are right in the middle of everything - Hilton, Sheraton, Hyatt, Embassy Suites, Alexander is a modern new place. There aren't really a lot of distinct downtown areas with the major hotels - they're all pretty close in proximity. Customers will have to deal with parking, which may be a minor issue. It's everywhere, but paid so some may skip it and stay on the outskirts of town for hobbying. All kinds of bars and restaurants within walking or very short cab rides.
Castleton is popular for ladies but is always a lil hot or a lil run down - not dangerous, just not upscale, and some places have been known to turn girls in. Just north of 465 has some decent places to choose from, like Carmel off Meridian or Fishers off I69. The airport area (Sam Jones Pkwy) has some decent spots and is calm.
Restaurants/bars: Yelp or TripAdvisor are pretty good here for ratings. Mass Ave has a number of places and is worth walking up and down. St Elmo's is well known for steak and famous for shrimp cocktail (blow your face off sauce). But there are a lot of options in Indy.
The best advertising boards are N R and B P (sadly), and the most active boards are at U S A S G. G B N has some Indy guys that are more willing to pay upscale prices, IMO.
Hope you have a great visit!