what research methods are u peeps using to get data etc. My main source of data is questionnaires. Focus groups and itnerviews etcwill also be used. I was told today that this wasnt good enough. If i do a survey - how many people is it worth getting etc? What are u people doing? I am a bit confused and in a bit of a daze as to where this is all going...

In terms of doing surveys, I take it you mean short questionnaires. In this case, the required number of questionnaires is determined by how you intend to analyse the data. For instance, if you only intend to slice and dice the whole sample then you'll need fewer, say 50 interviews.

If you intend to subdivide the respondents into groups and renalyse the data you will need alot more, depending on the level of detail you require in each.

Another caveat is where you're investigating a topic in which few people you survey are able to comment on the really juicy questions. So for example, if you survey 100 people, but only 10 people are able to answer a certain question you're not going to learn much. So a much larger sample is required.

I think it depends on the discipline you are working in. I know in my own area questionnaires are used as a way of getting basic info and idea of potential responses. But the main methods are interviews, focus groups and participant observation. Questionnaires are seen as rather 'undergraduate' by some staff members. As Sylvester points out, unless you are sampling a very very large number of people - questionnaires offer little depth. And in my opinion a PhD is about depth rather than breadth.

and what's a large number???

am definitely not gonna struggle with interviews.

100? 500? more??

Once again this depends on the field of study - but in terms of my own research, a questionnaire would be useful if I wanted to draw out some broad trends relating to UK Museums - thus sending a questionnaire to all local and national museums in the UK (not including private museums). This would mean over 250 questionnaires with potential response rate at 50%. Jojo not sure in what sense you mean struggle with interviews - but they offer vast amounts of data, AND in a shorter time period. You could always do a questionnaire, find out who is interested/looks interesting - and then target interviews from there.

there is no good or bad research method. as long as you can justify why you using this and not that method, everything goes.
The size of the sample for surveys depends on:
1) the size of the population (e.g. 200 respondents might be enough if your population is 1000 but not if it is 100000
2) what statistical methods are you going to use for analysis (if it is quantitative study (.e.g. there are certain rquairements regarding respondents and variables ration for regressions etc

But the most important thing is not how many people you have in your sample but how do you select them.

In general, it seems that reading some literature on research methods could be quite beneficial to solve your issue;)

forgot to add- and the choice of the method strongly depends on your research question and hypothesis:)