i am planning to travel to Europe for few months (4-6months), probably starts in July, 2007.
i am concerning the expenses if travel to Europe as i have limited budget.
therefore, i am hoping to get some advise the cheapest of below :
~~places which i should not miss out when travel in Europe.
hope to listen from all of you
For anyone to tell you places to not miss out, you will have to be a lot more specific as to what you are interested in, because what is a must see in my view may not be a must see in your view. Some people will say Amsterdam is a must see, but I would say Amsterdam is a see if you are in the region but otherwise don't bother. I say Rome is definitely a must see and Barcelona is also a must see. Russia (Moscow and St Petersburg are also must sees of the places I have been), but if you budget is low then Russia is probably not going to suit you, because it is a rather expensive country.
Cheapest way to get about would also depend on where you choose, how far in advance you can book etc. Like for such a long trip you wouldn't use a Eurail pass, but instead would rely on either seperate train tickets or budget flights (which is my prefered option). If you wait until Ryanair has a sale on to purchase your tickets and are flexible with your dates, you can get some bargain fares of like 0.01Euro plus taxes. If you leave it till the last minute to book, you will pay a lot more for it, but even then sometimes it is cheaper than buying a train ticket.
Cheapest accommodation well that is pretty obvious that unless you are taking a tent well a hostel is the cheapest option. You could also do a bit of couchsurfing or using the hospitalityclub website and try and get hosted by some families in the more expensive places, but it is a slight risk that you'd be taking but you'd probably have a very rewarding experience.
Have a great trip.
First thing you should do is go for a visa (unless you happen to have a EU pasport), because you are staying longer than 3 months.
Budgetflights is indeed the way to go, but you want to buy the tickets early if you want to get cheap prices, as you would be leaving in 2-3 months, this would be the time to do so.
Remember there is more than Ryanair, and Easyjet to choose from (about 70-80 companies offer budgetflights). If you book Ryanair than always make sure, where these flights are going. It can look cheap, but in a lot of cases, they are flying on Airports that are far away from the city, they tell. (e.g. Paris: they land on Paris Beauvais airport, instead of Orly or Charles de Gaulle, this means a much longer transfer to and from the airport, be sure there is an easy and cheap way to reach the city you want to go).
I agree with aharrold45, that you should give us, a little more to work with, what are your interests? (beach, parties, history, museums?).
But first the visa!!!