I start mine off around Christmas time in 15 cell trays and they stay in these till I plant them out (around March) and they are kept in my cold greenhouse so they don't really start to do anything till jan/feb anyway.
You can save your own shallots year on year TEB so you don't need to keep buying them. I started with half a dozen that were given to me and I've just bulked up the numbers I plant every year saving the ones that are a nice shape and roughly the same size. I don't show them but it's just as easy to keep good uns as bad uns