A good book on (general) ETL was just published, The Data Warehouse ETL Toolkit by Kimball and Caserta.
ETL can be coded using languages such as VB, but is most often done using a tool such as Informatica, Data Stage, Ab Initio, or one of the other (lesser) competitors.
Just like any job, ETL salaries depend on experience, market demand, etc. Most DW projects will have a lead ETL person sometimes called ETL Architect or maybe Lead ETL Developer. Guess which title usually gets paid more?
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The trouble with doing something right the first time is that noboby appreciates how difficult it was.
- Steven Wright