Entrance Fees
Although the visa costs a reasonable $30, there will be many additional fees. At Hargeisa airport, you must exchange $50 to Somaliland shillings at a bank rate so atrocious that you will surrender $25. On top of this covert bank fee is an entrance tax of $30. On the way out, you must pay $32 to leave the region. Fees may vary.
You need a Somaliland visa to enter--do note that Somali visas are not accepted. Most travellers get a visa in Addis Ababa in Ethiopia or the Somaliland Mission in London. You can get details from Somaliland government website (http://www.somalilandgov.com) or contact the Somaliland liaison office in Addis Ababa, phone +251 11 635921. To get to the office you should find the Awraris Hotel, and follow the dirt road that runs down the side of the hotel for 200 m, turn right, and continue another 200 m. A Somaliland visa is also allegedly available from the Somaliland representation in Djibouti. The unofficial Somaliland "embassy" in London will also issue a visa. The whole process is refreshingly unbureaucratic and can be handled by post, which makes London the most convenient place to get a visa for travellers who live in Europe and/or want to obtain a visa before travelling to the region.
By car
It is possible to enter Somaliland from Ethiopia by road. You can avoid paying many of the fees charged at the airport. However, if you plan to leave Somaliland by road it is advisable to make Ethiopian Visa arrangements multiple entry before traveling to Somaliland as the process of getting an Ethiopian Visa in Hargeisa can be quite cumbersome / time consuming Info from 2009: The Ethiopian visa in Hargeisa is easy to get, requires no paperwork and is available in one morning - cost $20.
Another option is the open border to the north to Djibouti. Info from 2009: Public transport 4x4s leave Djibouti every day in the late afternoon and travel across the desert throughout the night to arrive in Hargeisa the next morning. They leave from Avenue 26 in Djibouti City, at a price of DJF 5500.
Despite government efforts, there are still mines on some of the roads, look out for coloured rocks next to the road, if you see painted rocks DO NOT leave the Tarmac.