Salvete, omnes-- I have added several articles to the class website, including one on poems 12 and 13 ("Place Settings" and one on c.11 ("The Thematic Unity of Catullus 11").  There is also an article, "Passer as Passer," that discusses whether the sparrow poems represent poems about a pet bird, or contain an obscene allegory.  Below is Lesbia and her sparrow as imagined by the British painter Sir Edward Poynter.