12. A data processing apparatus for identifying a document within a block of text, comprising: a processor configured to: (i) tokenize a block of text into a plurality of text tokens according to at least one rule parser; (ii) compare each of the plurality of text tokens to a plurality of document tokens sequentially and determine if a text token matches one of the plurality of document tokens, wherein the plurality of document tokens correspond to one or more of a plurality of documents which have been tokenized according to the at least one rule parser; (iii) filter each matched text token according to predetermined filtering criteria to generate one or more candidate text tokens; and (iv) match a sequence of candidate text tokens from the one or more candidate text tokens to a sequence of document tokens, wherein the sequence of candidate text tokens occur in sequential order within the block of text.
12. A data processing apparatus for identifying a document within a block of text, comprising: a processor configured to: (i) tokenize a block of text into a plurality of text tokens according to at least one rule parser; (ii) compare each of the plurality of text tokens to a plurality of document tokens sequentially and determine if a text token matches one of the plurality of document tokens, wherein the plurality of document tokens correspond to one or more of a plurality of documents which have been tokenized according to the at least one rule parser; (iii) filter each matched text token according to predetermined filtering criteria to generate one or more candidate text tokens; and (iv) match a sequence of candidate text tokens from the one or more candidate text tokens to a sequence of document tokens, wherein the sequence of candidate text tokens occur in sequential order within the block of text. 14. A data processing apparatus according to claim 12 , wherein the plurality of documents include artist names, misspellings of the artists names, aliases of the artist names, song titles, misspellings of the song titles, and aliases of the song titles.