We've all got our opinions on raised beds which has been covered elsewhere, however I'll just throuw my comments in anyway. Raised beds take up a fair bit of time and money so I'd advise not jumping in straight away. Particularly as, like me, your veg plot will be part or your garden, rather than on another site, so aesthetics might be more important for you.
When taking on a new garden you'll want to get a feel for the soil, get to know how deep it is, are there any damp or boggy bits, where does the sunlight fall throughout the year, are there any sections that have a particular microclimate etc etc. You might even find a really useless bit that could quite easily take a path or another non-growing feature such as a shed (one of my paths for example follows the line of a ridge of chalk that lies just 4" below the surface).
Conversely after a year or two you might discover that a certain section would be perfect for permanent plantings such as a rhubarb patch/asparagus bed/permanent fruit trees etc etc. You'll then want to design your beds (raised or otherwise) around this.
So my advice would be to not use raised beds for the first year/ 18 months, if your're not inclined to go that way then garden conventionally, but if you are then adopt a 'lazy bed' system which will save time later, but not be disasterous if you decicde to carry on conventionally.
Hope this helps,
SS