1. A method of forming a target error model to facilitate spell checking input text related to a target data collection comprising steps of: a) providing a source query log containing user queries to at least one source data collection; b) generating target relational data based on the source query log including corrective substring suggestions that relate to the target data collection and corresponding misspelled substrings for the corrective substring suggestions extracted from the source query log, by applying a source error model to the source query log to thereby generate source relational data including corrective substring suggestions for misspelled substrings of the source query log, and selecting a subset of the source relational data that relate to the target data collection as the target relational data; c) building a target error model using the target relational data including target statistical occurrence data for the substrings of the target relational data derived from the source query log; and d) storing the target error model on a computer readable medium.