You didnt really need to restart the SQL Engine.

There are a few good resources abuiot, I have the MS press book :MS SQL Server Performance Tuning and optimisation, its a good starting point, another is Itzik Ben-Gans Inside MS SQL Server 2008, T-SQL querying, which gives a good over view of query tuning and how indexes work in Chapter 4.

There are plenty more but I've not read them.

If you hover over the Index Seek on the GMFPick.IX_GMFPick_5 icon on the plan, it shows you the columns in the Seek predicates list at the bottom, in this case CustomerIdNo.

As for the performance increase most of this will be down to the removal of the RID lookup which would have been very costly, especially with it being a heap lookup.

You might benefit from a clustered index on the IDNo on GMFPIck , but that could change the whole plan can leave you with other problems.

PS: Glad to hear you're safe (ish), I think a lot of people on this side (European) of the atlantic remember seeing the pictures after Katrina and wouldnt wish a similar event on anyone else.