Marion,
it's better to use a redwood, cedar or oak [if you have a decent budget - disease/ rot resistant] other than that a pressure treated pine or my favourite a rough sawn wood from a local timber yard [which you have to sand down].
Its rare these days to hear common use of spruce but it should/ would/ will make a lovely [grey-er-ish] deck.
As long as the timber is dried and free from splits, twists and soft edges, decay, knots etc. then any timber is good [ps give it a treat of garden preserve type paint first].
-my apologies I didnt know if you were just looking for a supplier/fitter or general info etc. and as a by-the-way i dont work for that firm. I hope this advice is as [excellent] useful as it usually is!
warm regards