I took a terrific spreadsheet that Johnny Select Seeds put together and offered up on their home page and added a little bit more to it.
I added a few more vegetables that they missed, a couple of usage notes on the first page and a harvest date tab to offer some guidance as to when things should be coming out of the garden and into your kitchen. Obviously using a model like this to predict the harvest is a little bit like trying to predict the weather – if you get close, you did all right.
The file is Excel and isn’t exactly the most dynamic approach – you have to update things on each page… ideally, I’ll get back to this and have a single page for the vegetables and then have the data dynamically sorted based on inputs on the first page… then again – Johnny Seeds saved me a lot of time with this jump start… and, uhh ohh… my leeks aren’t started yet! 
Take it or leave it – it’s a slightly polished for my own usage tool (so I can plan crop timings for the CSA) – I think gives a little more information than the original. Maybe… but I’m biased!
Here it is – Planting / Seed Starting / Harvest Target Workbook
Hello: Just a note to thank you for making your seed-starting plan available. I’m a fairly new vegetable gardener and I appreciate having this plan. Thank you.
No problem – I really hope it helps (and sorry it’s so ugly) – I really need to give credit to Johnny Select Seeds… really – I just stood on their shoulders!