sources for some of my genealogy assertions
For the situation with respect to Boniface of Tuscany, Beatrice of Bar/Lorraine, Matilda of Tuscany and Godfrey the Bearded, see "Europäische Stammtafeln zur Geschichte der Europäischen Staaten" (often just called "Europäische Stammtafeln", or even just "ES"). There are several editions, the one I got my information from was the older one edited by Frank, Baron Freytag von Loringhoven. There is also now a newer edition edited by Schwennike (spelling? first name?) but which I don't have good access to. From the Loringhoven edition, my information came from Vol. 1, Table 11, and Vol. 1, Table 12. On the web I can also see some of this information at
http://www.wikipedia.org/wiki/Matilda_of_Tuscany.
For Berthold of Zähringen, see ES Vol. 1, Table 9. (again, all references are to the Loringhoven edition, the one to which I had easiest access).
For Ernst of Austria (or Babenberg), his parents, and his wife, see ES Vol. 1, Tables 39 and 41.
For Richard of Aversa, and his father, see the genealogical table on p. 334 of "The Normans in Sicily", by John Julius Norwich. The pagination is for the paperback edition from Penguin books.
Another table a couple of pages earlier in the same book gives the name Fressenda to Robert Guiscard's mother.
For the parentage of Udo of Stade we are back to ES: see Vol. 1, Table 22.
The best source I have access to for the situation around the last years of the Lombard dynasty of Salerno is "Medieval European Coinage", Vol. 14 Italy (III) (South Italy, Sicily, Sardinia), by Philip Grierson and Lucia Traviani. See pages 57-58 for the political history of the principality in those years.