Padang Bai is where the main ferry terminal for boats to Lombok is located. Both slow and fast boats to Lombok and the Gilis can be boarded here. The bay is also used as the departure point by a lot of dive shops for trips to Nusa Penida and other off-shore dive sites. The town has a somewhat wild-west gritty feel to it, with lots of budget accommodations lining the bayfront, while dive boats and other craft line the beach. While Padang Bai does have a beach, unlike other East Bali destinations, it's still not a place I would recommend for a beach holiday. However, over the hill from the main town is the so-called "Blue Lagoon" area, which does have a nice beach without the industrial feel. That is where what appears to be the city's poshest resort is located, the Bloo Lagoon Village.
There is at least one ATM in Padang Bai, near the ferry terminal, that takes international bank cards. In addition, there are several other money changers around town. As elsewhere in Indonesia, small shops and restaurants do not take credit cards.
Padang Bai is full of small hotels and bungalows. Most of them are decidedly in the 'budget' category, appealing to backpackers and people who want to spend their money on diving rather than posh digs. The nicest place in town appears to be the Bloo Lagoon Village, located over the hill from the main part of town in the Blue Lagoon area.
Many of the restaurants around Padang Bai offer free Internet, at least outside of the main dining hours. There are one or two shops around town with computers if you didn't bring your laptop or other device. Expect to pay around 15,000 Rupiah an hour. Some hotels seem to have Internet, but not all of them, and some don't have wi-fi.