Getting a Visa is the foremost thing you need to look at, to work in UK.
You can apply for a Tier1 Visa that is granted to skilled migrant willing to work in UK .This Visa is not bound to any employer and you have the liberty of finding a prospective job even after you travel to UK. You need to score sufficient points in the Points based system to obtain this Visa.
You can find the details in :
Points Based System Tier 1, General Migrant (INF 21)
The other type of Visa is the Tier2 Visa for people coming to the United Kingdom with a job offer to fill a gap that cannot be filled from within the resident labour force. Here, the employer in UK should be willing to sponsor your visa . Intra company transfers also come under this category.
Points Based System Tier 2 (Skilled Worker) (INF 26)
All the details for obtaining visa can be found in the UK Border Agency site, and beware of fradulent agents who promise to get you a visa.
Taking the current job situation, finding a new job is quite difficult.
Hope this helps. All the best !!!!