Quattro, YABVU!
When I read your OP, I assumed that you would be looking for a child who was already of secondary school age. Given that you are looking for a younger child, and you are not tied to one geographical area, then the world is your oyster!
Simply find the secondary school that you like, then buy/rent accomodation within its catchment area. There are good comprehensives out there, but they will have a catchment area, which may change each year according to the number of applications. Catchment areas for small primary schools can be tiny, perhaps only a few streets. For most secondary schools you will be looking at distances greater than 1km, probably much greater than that in the area you are referring to. (I live in London, so obviously population density is much higher, and catchment areas will be smaller).
If you do this, then you will probably get the secondary school of your choice. You may not get the primary school of your dreams, but this is because primary classes are generally do not go over 30, so if the nearest school is full, then it is full. However, for 1-2 years a little bit of travelling will not hurt, and you may be lucky.
I am assuming that your dd would be in Y5 if in the UK (born between 1/9/99 and 31/8/00). If this is the case, then you would need to be in your new address by Oct 2010 to apply for secondary school. Generally state schools require proof of address with applications, and the fact that someone will definitely be moving into the area at a later date will not impress admissions staff (unless you go private, then they will not care where you live so long as you pay the fees).