I am looking for a list of providers and prices for broadband internet
in Spain. One important detail, i need an upstream of 768 kb/s or
higher.

Here is a list of Spain ISP's with their dial-up services and dedicated services:

Dialer.net 	ISDN, 33.6, 28.8, 56K

Ibernet Telematica 	ISDN, 33.6, 28.8, 56K 	Frame Relay, DSL

Netaway 	ISDN, 33.6, 28.8, 56K 	Frame Relay, DSL

VPM Internet Services, Inc. 	ISDN, 33.6, 28.8, 56K 	T3, Frame Relay,
FracT3, T1, DSL

Let me know if I've been of any help

sorry forgot about pricing:

Dialer.net:    	 Pay as you go. No setup fee. No monthly fee

Ibernet:         Individual Access .... $110 / year Corporate Access
..... $100 / month Web Hosting ........ $33/month Housing
.............$33/month

Netaway:  No monthly charges. Just pay for the calls you make and the
usage of the service.

VPM Internet Services, Inc.:       http://www.vpm.com/?q=more_business_solutions

I may be able to assist you further if you can provide the following details:

1) Which area of Spain are you interested in? (In many rural areas
broadband is not yet available.)
2) Usually most European ISP's require clients to sign for a minimum
12 month contract.
 

I will be in Seville tomorrow and Sunday and can further check details.

Wanadoo: all spanish territory - 20mb/1mb + national calls - 36?/m -
http://www.wanadoo.es/
Jazztel: " - 20mb/1mb + national calls - 29.95?/m - http://www.jazztel.com/

Those have the most availability on spain, i hope this can help you