have ascertained all shields are working now so it seems the sms controller sketch may be the fault
steep learning curve here... i've managed to from scratch figure out how to upload & use serial monitor to arduino & manage the sms messages on the gprs/gsm shield(with a little help)...so i should be able to get my head around the sketch...
success at last... in an in intuitive moment i was considering the role of the reset button on the arduino board...acting on a hunch i uploaded the necessary sketch & assembled the shields then hit the reset button to start the uploaded sketch...sent the appropriate text... bingo the relay tripped!!!
as a side note... i eventually found the book i should have started with "getting started with arduino. second edition"... a must get for anyone looking to try these cute lil micro processors