Did those potential customers who you spoke to use Google when finding who to go out to tender to?
I don't know anything about your business, but are there industry tendering sites/processes you are involved with?
Is your business local?
What search terms are your customers likely to use?
How much competition is there for those terms?
Would you have to compete using PPC (pay-per-click) ?
Where do you get your business currently? Word of mouth, referrals, previous contracts, trade publications etc ?
Obviously this information isn't for me! But I believe it would be worthwhile to think about this thoroughly before diving into putting up a website.