Visit Visas:
Requirements for obtaining a visit visa for Dubai vary depending on your nationality. GCC citizens do not require a visa to enter Dubai, and citizens of 33 other countries can get a visa on arrival at Dubai International Airport. Nationalities not in this list can get a 30 day tourist visa sponsored by a local entity, such as a hotel or tour operator, and this should be obtained before entry into Dubai.
In general, visit visas are valid for either 30 days (short term visit visa) or 90 days (long term visit visa). Both visas are non-renewable. Fees for short term visa are AED 620 application fee + typing fee and for long term visa, it is AED 1120 application fee+ typing fees. Also a deposit of AED 1000 is to be paid by the local sponsor/relative/resident which can be reimbursed after the visit visa holder has left the country.
Multiple-entry visas are available for visitors who have links with local businesses that require them to visit regularly. Multiple-entry visas are valid for visits of a maximum of 14 days each time, for six months from date of issue. It costs AED 2,100 (plus AED 20 delivery fee) and should be applied for after entering the UAE on a visit visa.

Transit Visas:
Visitors travelling through Dubai in transit, a special transit visa is available free of charge through certain airlines. It is valid for 96 hours.

Employment/ Residence Visas:
In order for any non-UAE national to work and live in the UAE he or she is required to hold a valid work permit and residence visa. The Ministry of Labour is responsible for issuing work permits and the Naturalisation and Immigration Department of the Ministry of Interior is responsible for issuing residence visas.
Prior to an employee entering the UAE the employer should apply for an employment visa which is valid for 2 months. Upon arrival in the UAE, the employee must obtain a health card and thereafter attend a Government hospital for a blood test. Provided the results of the blood test are clear, the Ministry of Labour will issue a labour card which will enable the employee to obtain a residence visa. Residence visas are usually valid for a period of 2 years.
It is possible to obtain a residence visa through ownership of freehold property, but there are a number of pre-conditions, and the visa is of limited duration. It is thought that this issue may be re-considered by the authorities if it is felt appropriate or necessary to stimulate the economy by encouraging population growth.

Business, Accommodation, and Travel
Please refer to the following sites:
http://www.dubaitourism.ae
http://www.justdubai.org/