I'll give you my experiences of who purchases what. It's important to remember the web hosting industry is very diverse, both in terms of web hosts and web hosting customers. Web hosts are generally male, with an increasingly lower average age due to teenagers - there are however several high-profile hosts run and owned by women. People using webhosts are the people next door, down the street, and over the hill
"website + design/coding + maintenance" – local folk, mainly business people but also a few locals who’ve setup fairly popular sites and don’t have a clue what to do now that they are so popular

25-40, male *and* female people fit in this category for me. As an aside, I must say, the women are always much easier to deal with – once you’ve built up a relationship with them as a customer, they seem to accept things more easily than my male customers, who like to question and examine everything in crazy amounts of detail! Guess which lot get the cheaper bills at the end of each month…

I guess having both groups is good - women for making things easy, and males for asking questions allowing you to increase their invoicables each month.
“my $50 server bucket” – teenagers mainly. Not really targeting them, but, it’s who I end up with

There are a few people who also rent them out as testing grounds. Age is probably 10-20, and most certainly male.
“$100-200 servers... getting somewhere” – male, 15-50.
“$250+ servers” – women get another look in here, couldn’t tell you which age group I land up with.
Overall, I simply target those people who are willing to pay cash. Running multiple brands and multiple products leaves it pretty wide open – each gets a certain type of people in, but it all balances out in the end.
My quick summary:
The cheaper something is, the more likely teenagers rush to the scene. Women seem more likely to go somewhere based on recommendations (word of mouth etc...), and men seem to weigh everything up over a few months before deciding.