I went with a few of my coworkers last August. We decided to hire a tour guide and car/van for the 5 of us. It was very cheap and it helped to have a tour guide with us (we went to the Agra Fort, had a great lunch, learned a lot of the history, etc etc).

We stayed at the Oberoi Amarvilas--it was AMAZING! I highly recommend staying there not only because it's a very luxurious, but also because it's the closest hotel to the Taj. Every room faces the Taj, and almost every room has a balcony. We enjoyed watching the sunset over the Taj and hearing the prayers in the background.

Don't go in August if you can't help it--it's HOT!!! To fight the heat, we visited the Taj at 6AM. Try to go early regardless, because you'll be able to avoid the crowds and get the Taj all to yourself.

Please contact me if you'd like more information on the tour company that we used.