Sevilla is a well connected city, with modern and convenient infrastructures and means of transportation.
By plane Sevilla's international airport, San Pablo, has direct flights with most of Spain and the main European cities, such as Rome, Milan and Florence in Italy; Paris in France, London and Liverpool in England; Dublin in Ireland; Frankfurt in Germany; Amsterdam in Holland and many more. Most of the airlines covering these routes are "Low-cost" airlines, you could get round-trip tickets for about 50-100€ (70-130$).
By train Sevilla's Railway Station, Santa Justa, has connections with the main Spanish cities, by regular trains, or by the modern high-speed train AVE, which takes you to Madrid in 2hrs 20mins.