JNP
The entrance is about 100m beyond Oak Close. There is a stop at the end of Oak Close - Just ask for the Baginton Oak (Both a tree and a pub). From the Airport entrance it is five minutes walk to Dakota House although the entrance is airside so you would probably need to ring them (or get the person at the security point to) to get someone to take you through.
Incidentally, coming out of the station turn left and take the footpath between station building and car park. One minute to Warwick Road bus stop.