The problem with place-names is that they tend to be highly conservative in their spelling, unlike common nouns, so that it's never clear exactly when a sound may have dropped out. Just occasionally there is orthographic evidence, and a good example is Gloucester. Was the modern pronunciation there in Shakespeare's time? The answer is definitely yes.
In the First Folio, Gloucester is spelled in three ways: as Gloucester (33 times), but much more often as Glouster (38), and Gloster (109). Sometimes you get the variant spellings within a few lines of each other. Similarly, Gloucestershire is spelled thus (3) alongside Gloustershire (2). And the fact that it was a disyllabic pronunciation is evidenced by the metre, as in Richard II (2.1.128), where we read: 'My brother Gloucester, plaine well meaning soule'.
No such evidence in the First Folio for Warwick, Norfolk, and Suffolk, unfortunately. Here one needs to look at other sources to see if there are spellings without the w or l. Certainly folk (as a common noun) was being spelled without the l from as early as 1400. Old place-name derived surnames, such as Worrick and Worricker, date from the Middle Ages. Informal texts, such as transcriptions of statements in court, are likely to show everyday pronunciations in the spelling. For instance, in Text 57 of Bridget Cusack's Everyday English 1500-1700 - a splendid resource - we find a 1628 presentment made by churchwardens from Stratford-upon-Avon where Warwick is spelled warrick.
Any other examples welcome.