Already identified as Scilla lucilliae (syn Chionodoxa)

I agree it's Chionodoxa,

Thank you for the responses. Now to find a supplier.

These need to be planted in the Fall. Anyplace that sells Spring flowering bulbs should have these available.

Most places that sell bulbs will have them, as will most mail order garden suppliers.

If you already have them in the garden, then they will seed themselves around pretty quickly. Flowering from sowing takes a couple of years. You could also dig up the clumps when the leaves die down and split up the clumps. They very soon clump up again.

Updat. Thanks a lot for all the info. Got a few of the bulbs last year from RHS and planted out and this spring have had a lovely display of blue flowers everywhere. Thanks again.

There are also white and pink versions of them as well.

Just to say thanks. Got a load of these bulbs from RHS and planted them. Really lovely displays along with the crocuses. Hopefully they will spread.