Is there a program to tell me if a specific parts list is available in a given colour? I want to build some models using the new 1x2 curved slopes which come in limited colours at the moment, the models need to have single solid colours if at all possible.  

Is there a program or site that will let me put in the parts needed and preferred colour, and then tell me if they are all available in that colour?

I know about Bricklink and Brickset (but not a registered user of either), so I can do it part by part if I need to.  I could also use LDD Manager to get a list of buyable bricks from a LDD file containing all bricks in all colours, although I would still need to check another site to find out what sets they are in.

Is there an easier way?
If you're up for a bit of programming, Rebrickable.com has an API that can query part+colour and return matching sets.

Get Part Sets
Use this service to get a list of all sets that a specific part/color combination appears in. This is best used after calling the get_part function to retrieve the list of available colors.
URL    /api/get_part_sets
Method    GET
Parameters    key - API Key
part_id - The Part ID to look up (e.g. 3001)
color_id - The LDRAW based Color ID to look up (e.g. 0 = black)
format - How to display output data. Valid values: xml, json
Returns   INVALIDKEY - The API Key is invalid
NOPART - The part/color could not be found or has no sets
 Output data.