From Bima you can take a local bus (25.000 rp, first one 5 am, last one 5 pm) directly to Labuhan Sape, the ferry port. Other options are available to the town of Sape (bemo for 15,000 rp from Bima) or you can also charter a bemo for 200.000. Just make sure that they won't put you onto another cramped bemo after 10 minutes.
Most people come here to catch the slow (daily) or fast (three times a week) boat to Labuan Bajo on Flores. The fast boat also goes to Sumba twice a week. Call Kapal Cepat Express Bahari 0823 592 87 257 in Sape, 0822 373 68 767 in LB or 0812 3743 6447 in Waikelo (Sumba).
Warung Barokah, Jl. Pelabuhan Sape (Next to Losmen Mutiara. If you come from the ferry it's on your left hand, just after you passed the gate.). Nice clean Warung. Serves Bakso and Soto Ayam. Comes with a big plate of plain rice.10.000. edit
Arema Sape, Jl. Pelabuhan Sape (500 mtr. from the harbour gate on your left hand), ☎ 037471015. This place serves a lot of fish dishes, but also mie goreng and nasi goreng (not on the menu, just ask for it). There is also an internetcafé inside if you need to spend time, waiting for the ferry. edit
Losmen Mustika, Jl. And. Pelabuhan Bugis Sape (If you walk from the ferry onto the pier, it's about 1 km. further on your right hand, just into a small street. Look out for the sign on the corner of the street), ☎ 037471227. checkout: 2pm. Nice losmen, about 1 km. from the harbour. The rooms for 75.000 have fan and squat toilet, the ones for 150.000 have AC and Western toilet. The beds in the AC rooms are better then in the cheaper ones. They serve breakfast (not included) and dinner, if you order it 1 day in advance.Fan 75000, AC 150000. edit
Losmen Mutiara, Jl. Pelabuhan Sape (Just next to the harbour gate), ☎ 037471337. edit
Hotel Mantika, Jl. Pelabuhan Sape (Just next to Losmen Mutiara.), ☎ 037471178. 150.000 - 250.000. edit
Losmen Nusa Bajo, Jl. Pelabuhan Sape 4 (This losmen is not on the pier like the others, but about 2,5 km. from the harbour. If you walk from the pier to Sape, it's on your left hand.). It has basic cheap rooms, with bathroom inside. The bathroom includes a squat toilet and no shower... 50.000. edit
From Sape you can get the ferry to Labuan Bajo on Flores (once a day, departure at 9 am). The ferry does not run if there are high waves or storms, so make sure you are informed before you come to Sape.